The 490-day, 1260-day, 1290-day, 1335-day, and 2300-day prophecies each represent those time periods in years, following the day-for-year prophetic principle specified in both Numbers 14:34 and Ezekiel 4:6.
Prophetic Day-for-Year
After the number of the days in which ye searched the land, even forty
days, each day for a year, shall ye bear your iniquities, even
forty years, and ye shall know my breach of promise. (Numbers 14:34,
KJV)
And when thou hast accomplished them, lie again on thy right side, and
thou shalt bear the iniquity of the house of Judah forty days: I
have appointed thee each day for a year. (Ezekiel 4:6, KJV)
The 2300-Day and 490-Day Prophecies
The 2300-day prophecy of Daniel 8:14 began in 457 BC with the commandment to restore and rebuild Jerusalem, recorded in Ezra 7. The first 490 years of that prophecy were specified separately as marking the time until the Messiah would come and be crucified. This 490-day portion of the prophecy is outlined in Daniel 9.
And he said unto me, Unto two thousand and three hundred days; then
shall the sanctuary be cleansed. (Daniel 8:14, KJV)
Seventy weeks are determined upon thy people and upon thy holy city,
to finish the transgression, and to make an end of sins, and to make
reconciliation for iniquity, and to bring in everlasting
righteousness, and to seal up the vision and prophecy, and to anoint
the most Holy. (Daniel 9:24, KJV)
So the 490-day and 2300-day prophecies start simultaneously--the 490 (seventy weeks) is just the first part of the 2300.
The 1260-Day Prophecy
And I heard the man clothed in linen, which was upon the waters of the
river, when he held up his right hand and his left hand unto heaven,
and sware by him that liveth for ever that it shall be for a time,
times, and an half; and when he shall have accomplished to scatter
the power of the holy people, all these things shall be finished.
(Daniel 12:7, KJV)
One "time" is a year, as can easily be deduced by comparing the parallel passage in Revelation which prophesies this same time period, beginning in chapter 11 and proceeding through chapter 13. Consider especially Revelation 12:6 which specifies "a thousand two hundred and threescore days" followed by verse 14 which mentions the "time, and times, and half a time" and Revelation 13:5 which speaks of this as "forty and two months." Each month, Biblically, has 30 days, so 42 months amounts to 1260 days, i.e. three and a half years.
The 1335-Day and 1290-Day Prophecies
11 And from the time that the daily sacrifice shall be
taken away, and the abomination that maketh desolate set up, there
shall be a thousand two hundred and ninety days. 12 Blessed
is he that waiteth, and cometh to the thousand three hundred and five
and thirty days. (Daniel 12:11-12, KJV)
(NOTE: The translation of the verb "set up" in verse 11 is imprecise. The Hebrew Qal infinitive here can mean something that is continuing or ongoing, something still in progress.)
Both the 1335-day prophecy and the 1290-day prophecy began in AD 508 when Clovis defeated the Visigoths and launched his campaign to establish the papacy. For a period of thirty years, the setting up of the "abomination that maketh desolate" (Daniel 12:11) continued, until AD 538 when the papacy officially assumed its civil power, at which time the 1260-year period commenced.
Prophetic Endpoints
In AD 1798, the 1260-year and 1290-year prophecies ended with the capture and subsequent death in captivity of the pope in Rome who was taken by General Berthier of Napoleon's army. This ended the 1260-year political reign of the papacy which had officially assumed civil power in AD 538 (popes existed well before this, but had only had religious authority).
But the 1335-day prophecy continued to AD 1843. It was in this year that, due to the teachings of William Miller in America, whose message had spread to Europe and beyond, being published in the newspapers of the time, a movement of people expected their Lord to return. These people, though destined to suffer a great disappointment, were truly blessed in that year with making heart preparations for Jesus' coming. They truly believed the prophecy was to end with Jesus' return--but, though correctly calculating the time, they had mistaken the event. The "sanctuary shall be cleansed" did not refer to the earth, as they supposed, but to the sanctuary in heaven which had been stained with the record of sin throughout earth's history. It was into the Most Holy Place of the heavenly sanctuary that Jesus was to go, officially beginning his ministry of cleansing. Because of their faith, they had put away every sin, confessed their faults to one another and forgiven each other, and had prepared in every way possible to meet their Master. Their characters and lives testified that they had been in communion with Jesus; in this they were truly blessed, even as the prophecy indicated.
The 2300-day prophecy, however, extended to 1844, one year beyond 1843. Why the year of difference? Because the early calculations of those expecting Jesus' return in 1843 were found to be mistaken on account of having neglected that there was no zero year between BC and AD dates. For one year, from 1843 to 1844, they enjoyed peace with God and were joyful in the expectation of Jesus' return, recalculated to be October 22, 1844--the day on which the Jewish day of atonement was to fall in that year. The prophecy in Revelation 10 about eating the "little book" and its taste being very sweet in the mouth, but becoming bitter in the belly, applied to this group of people--but they were not to see this until afterward. The prophesied disappointment must come.
After 1844, no further times were marked out in prophecy. Indeed, Revelation 9:5-6 indicates that prophetic times would be ended. From 1844 to the coming of Christ there is to be no further prophecy giving us a definite time for end-time events. For example, no one will know when probation has closed, when the seven last plagues will come, or the date of Jesus' return. The 2300-day prophecy, which spanned the 490-, 1335-, 1290-, and 1260-day/year prophecies, was the longest and last of these.
So, in chronological order, we can list these prophecies as follows:
Year |
Commencement |
Fulfillment |
Associated Event(s) |
457 BC |
2300-day prophecy 490-day prophecy |
|
Commandment to restore/rebuild Jerusalem |
AD 34 |
|
490-day prophecy |
Stoning of Stephen, marking the end of Jewish probation--gospel goes out to Gentiles |
AD 508 |
1335-day prophecy 1290-day prophecy |
|
Clovis, King of Franks, destroys Visigoth opposition, embarks on establishment of papacy |
AD 538 |
1260-day prophecy |
|
Papacy officially established |
AD 1798 |
|
1260-day prophecy 1290-day prophecy |
Papacy receives "deadly wound" (see Revelation 13:3); Pope taken captive and removed from Rome by Berthier, one of Napoleon's generals--pope soon afterward dies in captivity |
AD 1843 |
|
1335-day prophecy |
The time of the blessed (Daniel 12:12) who expect Christ's imminent coming |
AD 1844 |
|
2300-day prophecy |
Jesus enters Most Holy Place in heavenly sanctuary to begin his work of atonement as our High Priest; beginning of earth's final "Day of Atonement" |
These can also be represented in timeline chart format as shown below.

Conclusion
Yes, the 1290- and 1335-day prophecies start at the same time.
Blessed is he who waits and arrives at the 1,335 days.
- at the end of 1,335 something good happens. The previous sentence is about the setting up of the abomination; context gives plenty of clues what it COULD be. Is there a Jewish feast that has to do with abomination and cleansing?John 10:22–23
- Hannukah. It wasn't in Old Testament because it happened after Old was written but the fact it was mentioned in New Testament surely must make it (potentially) relevant.