Based on the research your question spurred, I would have to answer no, the Last Supper was not considered a Passover Feast in the early Church.
From the wording of your question and the examples you cite, we will take the period of “Early Church History” to span from the times described in the Acts of the Apostles until 430 (the year of Augustine’s death).
First, we must consider what the inclusion of John 19:14 in the Gospel implies of the beliefs held by the Church Fathers. Some hold that the verse read, quoting from the Orthodox Patriarchal Text:
ἦν δὲ παρασκευὴ τοῦ πάσχα, ὥρα δὲ ὡσεὶ ἕκτη
meaning (Orthodox New Testament translation):
Now it was the preparation of the passover, and about [the] sixth hour
According to the apparatus of the 11th edition of the Nestle-Aland Greek-English New Testament, this reading is very close (excluding punctuation and accents, of course), to that found in the majority of manuscripts consulted in the 27th revised edition of the Greek text (some indicate δὲ ὡσ instead of δὲ ὡσεὶ). The Nestle-Aland Greek New Testament (the “Critical Text”), 27th edition, opts for a slightly different reading:
ἦν δὲ παρασκευὴ τοῦ πάσχα, ὥρα ἦν ὡς ἕκτη
using the preposition ἦν instead of δὲ.
Metzger’s Textual Commentary on the Greek New Testament (2nd ed.) indicates that a number of manuscripts, including the 4th century Codex Sinaiticus and the 5th century Bezae Codex, read “about the third hour” instead of “about the sixth hour” (ὥρα … ὡς τρίτη). He hypothesizes a transcription error between the Greek numerals for 3 (Γ) and 6 (ϝ) could account for the discrepancy.
There is no indication, however, that any manuscript in the Nestle-Aland corpus containing John 19:14 exists which states something other than Now it was the preparation of the passover (ἦν δὲ παρασκευὴ τοῦ πάσχα), nor is there any indication that any manuscript in the Nestle-Aland corpus excludes the verse altogether. Based on this evidence, we assert:
(Proposition I) Any Church Father reading the Gospel of John would have read in the Gospel that Jesus appeared before Pilate on the day
of Preparation of the Passover.
If we make the further assumption that any Church Father considering the Gospel of John for inclusion in the New Testament canon would have actually read the Gospel in its entirety, then we should be able to infer that, unless the Father specifically wrote something rejecting John 19:14 as represented above, that he accepted the passage as being truthful in some sense.
I qualify my above statement with “in some sense” because, contrary to what many might believe, strict inerrancy in the sense that every single statement in the Bible is factually true, was not a principle held by the early Church Fathers (i.e. through the mid 5th century). As John Chrysostom wrote, the Evangelists are “in many places are convicted of discordance” (Homily I on the Gospel According to Matthew). Nonetheless, I think we need enumerate those Fathers who supported the inclusion of the Gospel of John into the New Testament as a piece of inductive (not deductive) evidence. They would have certainly considered the truth or falsity of John 19:14 in their decision. These Fathers include, at a minimum:
Athanasius the Great (296-373), 39th Festal Letter, written in 367.
Cyril of Jerusalem (313-386), Catechetical Lecture IV.35, written around 350. Cyril writes of “four Gospels” but does not mention them by name, but we assume that he was in accord with other Church Fathers in including John.
The Church Fathers present at the 3rd Council of Carthage (397)
This leads to a second proposition:
(Proposition II) Athanasius, Cyril of Jerusalem, and the Church Fathers assembled at the 3rd Council of Carthage accepted the Gospel
according to John (including John 19:14) as belonging to the New
Testament Canon
The verse in John (19:14) - including the reference to passover - is considered in the writings of Tatian (120-180), Peter of Alexandria (300-311) and Augustine. Hippolytus (170-235) mentions the verse in the second chapter of his fragmentary work on Daniel, but refers only to the “sixth hour”.
John 19:14 is quoted in its entirety in the Tatian’s Diatessaron, an early harmony of the Gospels originally written in Syriac. I know that Ephraim of Syria (306-373) wrote a commentary on the Gospels following Tatian’s Diatessaron, but unfortunately I lent my copy of an English-language translation of his commentary to someone. I do not recall Ephraim observing any kind of discrepancy in the timing of passover with respect to Christ’s Passion, but this is from memory.
Peter of Alexandria is somewhat ingenuous towards “some who, carried along by ignorance, confidently affirm that after He had eaten the Passover.” He emphatically denies that Christ ever ate the Passover supper: “He did not eat of the legal Passover.” The full text of his discussion is found in the first chapter of his fifth fragmentary writing:
But after His public ministry He did not eat of the lamb, but Himself
suffered as the true Lamb in the Paschal feast, as John, the divine
and evangelist, teaches us in the Gospel written by him, where he thus
speaks: Then led they Jesus from Caiaphas unto the hall of judgment:
and it was early; and they themselves went not into the judgment-hall,
lest they should be defiled, but that they might eat the passover
[John 18:28]. And after a few things more. When Pilate therefore heard
that saying, he brought Jesus forth, and sat down in the
judgment-seat, in a place that is called the Pavement, but in the
Hebrew, Gabbatha. And it was the preparation of the passover, and
about the third hour, as the correct books render it, and the copy
itself that was written by the hand of the evangelist, which, by the
divine grace, has been preserved in the most holy church of Ephesus,
and is there adored by the faithful. And again the same evangelist
says: The Jews therefore, because it was the preparation, that the
bodies should not remain upon the cross on the Sabbath-day (for that
Sabbath-day was an high day), besought Pilate that their legs might be
broken, and that they might be taken away [John 19:31]. On that day,
therefore, on which the Jews were about to eat the Passover in the
evening, our Lord and Saviour Jesus Christ was crucified, being made
the victim to those who were about to partake by faith of the mystery
concerning Him, according to what is written by the blessed Paul: For
even Christ our Passover is sacrificed for us [1 Corinthians 5:7] not
as some who, carried along by ignorance, confidently affirm that after
He had eaten the Passover, He was betrayed; which we neither learn
from the holy evangelists, nor has any of the blessed apostles handed
it down to us. At the time, therefore, in which our Lord and God Jesus
Christ suffered for us, according to the flesh, He did not eat of the
legal Passover; but, as I have said, He Himself, as the true Lamb, was
sacrificed for us in the feast of the typical Passover, on the day of
the preparation, the fourteenth of the first lunar month. The typical
Passover, therefore, then ceased, the true Passover being present: For
Christ our Passover was sacrificed for us, as has been before said,
and as that chosen vessel, the apostle Paul, teaches.
Augustine comments on John 19:14 in On the Trinity, On the Harmony of the Gospels, and in his commentary on John, but the only discrepancy he seems to be concerned with is the discrepancy that appears between Christ's being crucified at the 3rd hour, as reported in Mark, and the 9th hour as reported by the other Evangelists. In his 117th Tractate on John, Augustine does not seem to contest that the Crucifixion took place before the passover and not after it. He writes:
And it was the parasceve of the passover, about the sixth hour. And parasceve is in Latin praeparatio (preparation); but the Jews are
fonder of using the Greek words in observances of this sort, even
those of them who speak Latin rather than Greek. It was therefore the
preparation of the passover.
(Frankly I am not sure I follow what Augustine is getting at with his references to Latin or Greek, but he seems to indicate he believes that the events described took place prior to Passover).
These are the sum of discussions I can find regarding the reference to “preparation of the passover” in John 19:14 in the writings of any Ante-Nicene
or Nicene and Post-Nicene Father in the time period we are considering (i.e. any Father whose writing is included in Schaff’s ANF and NPNF series).
Thus, I would propose a third proposition:
(Proposition III) The writings of the Ante-Nicene, Nicene or Post-Nicene Father seem to confirm rather than dispute the literal
meaning of John 19:14 - that Christ was crucified prior to Passover.
In your question you refer to part of an Article found in Thomas of Acquinas' Summa Theologiae (Part III, Question 46, Article 9), "The time of the Passion". The Objection that Acquinas is addressing is:
It would seem that Christ did not suffer at a suitable time. For
Christ's Passion was prefigured by the sacrifice of the Paschal lamb:
hence the Apostle says (1 Corinthians 5:7): Christ our Pasch is
sacrificed. But the paschal lamb was slain "on the fourteenth day at
eventide," as is stated in Exodus 12:6. Therefore it seems that Christ
ought to have suffered then; which is manifestly false: for He was
then celebrating the Pasch with His disciples, according to Mark's
account (14:12): On the first day of the unleavened bread, when they
sacrificed the Pasch; whereas it was on the following day that He
suffered.
You quote part of Aquinas reply to the objection, but only the portion that illustrates Jerome's statement as possible support for the objection. The whole of his "Reply to Objection 1" is in five paragraphs and addresses not only what Jerome wrote but also possible arguments in the writings of the Gospels and John Chrysostom.
Possibly additional support could be found in other patristic writings for arguing that the Last Supper was not, in fact, the Passover meal, but I think that what I have stated in the three propositions and tried to demonstrate should be adequate to infer what the early Church believed.
This also fits with the approach of Caleb's meta on how to draw the line between BH and Christianity Stack Exchanges, "Hermeneutics.SE would be the place to discuss the various hermeneutical methods, deal with textual and historical criticism, and cover historical interpretations as they relate to the understanding of texts, etc."
(From : hermeneutics.stackexchange.com/questions/22071/…); B.) But, I agree that a verse from John should have stayed in; It's back, and fixed!