It often helps to begin as close to the text as we can, avoiding bringing in ideas that the author may not have understood or intended. If we approach a text with a fixed idea in mind about what a key term (like 'The Day of the Lord') means, we may miss what's going on. Like many prophecies in scripture, we also shouldn't assume that it's only referring to one event. There are many moments of judgement throughout history that passages may refer to.
Context: Jeremiah 29
Chapter 30 follows many chapters of gradual revelation about the Exile - the coming judgement of YHWH and what that means for God's people and the city of Jerusalem. The first wave of Exiles has already left, and more will follow. In chapter 29 Jeremiah has written a letter of encouragement to those already in Babylon, and we have heard YHWH's urging to His people to settle and increase in Babylon.
The Passage: Jeremiah 30 (NIV)
5 “This is what the Lord says:
“‘Cries of fear are heard—
terror, not peace. 6 Ask and see:
Can a man bear children? Then why do I see every strong man
with his hands on his stomach like a woman in labor,
every face turned deathly pale? 7 How awful that day will be!
No other will be like it. It will be a time of trouble for Jacob,
but he will be saved out of it.
This is grounded in the coming fullness of Exile - over the next nine chapters of Jeremiah things will continue to go from bad to worse, as Jerusalem and its leaders reject the word of YHWH and it is eventually burnt to the ground. The book of Lamentations will soon follow, expressing the extreme sorrow and pain felt by Jeremiah and the rest of the survivors. However, a further day of hope will follow:
8“‘In that day,’ declares the Lord Almighty,
‘I will break the yoke off their necks and will tear off their bonds;
no longer will foreigners enslave them. 9 Instead, they will serve the Lord their God
and David their king,
whom I will raise up for them.
10 “‘So do not be afraid, Jacob my servant;
do not be dismayed, Israel,’ declares the Lord. ‘I will surely save you out of a distant place,
your descendants from the land of their exile. Jacob will again have peace and security,
and no one will make him afraid.
So first of all, this is clearly talking about the Exile of Judah to Babylon.
But it's only a Partial fulfilment
In the immediate sense, Jeremiah 30 speaks to the immediate Exile, and the restoration which will soon follow - YHWH will regather His people from the nations, and across Ezra, Nehemiah, Haggai, Zechariah and other texts we will learn more about that moment. However, the fulness of Israel is never regathered, the Kingdom is not fully re-established, and it never reaches the fullness that is described here:
9 Instead, they will serve the Lord their God and David their king, whom I will raise up for them.
This is what everybody was hoping for - the crowning sign of the Kingdom's restoration. We see glimpses of it in Zerubbabel's return to Jerusalem as David's heir, YHWH reaffirms his promise through him in Haggai:
Haggai 2:23 "“‘On that day,’ declares the Lord Almighty, ‘I will take you, my servant Zerubbabel son of Shealtiel,’ declares the Lord, ‘and I will make you like my signet ring, for I have chosen you,’ declares the Lord Almighty.”"
Zechariah delivered similar prophecies, affirming Zerubbabel as YHWH's chosen instrument:
Zechariah 4:7 “What are you, mighty mountain? Before Zerubbabel you will become level ground. Then he will bring out the capstone to shouts of ‘God bless it! God bless it!’”
And so at first Zerubbabel is somewhat exalted, but never becomes a full King of Jerusalem, nor does this happen in the centuries that follow, and Israel is left longing for the King that YHWH will raise up, and this generated the Messianic expectations present in Jesus' time.
Towards Full fulfilment
Interestingly, Zechariah's prophecies included far more than Zerubbabel:
Zechariah 6:11 Take the silver and gold and make a crown, and set it on the head of the high priest, Joshua son of Jozadak. 12 Tell him this is what the Lord Almighty says: ‘Here is the man whose name is the Branch, and he will branch out from his place and build the temple of the Lord. 13 It is he who will build the temple of the Lord, and he will be clothed with majesty and will sit and rule on his throne. And he will be a priest on his throne. And there will be harmony between the two.
Again, we encounter a prophecy with multiple layers - there was a physical man called Joshua son of Jozadak, who did contribute to the rebuilding of the Temple, and brought some unity to Jerusalem. However, he was not a King, and established no harmony between priesthood and kingship - these things were reserved for another.
Ultimately, it was another Joshua, a future King who would be raised up, who would be high priest and bring harmony between Kingship and priesthood, to whom all these prophecies meet their greatest fulfilment.
In a nutshell, yes this is The Day of the Lord, in that it describes the judgement of Exile that fell on the people in Jeremiah's day. But if you take the term to mean only the Day that is foretold to come beyond the resurrection of Christ, then no, I don't think there's a clear prophecy here about that moment. That does not mean that other prophets and texts didn't build on it to include that moment, but that isn't the sense that we get from Jeremiah.