Hello @straberiwine,
I am still relatively new to Monday, this may actually be my first post, so this may not work for you, but I just wanted to share what I use for a similar situation. I have a board with columns for a Date that we need to document and then columns for Q1, Q2, Q3, Q4 dates to trigger automations.
I use a series of automations based on the quarter dates to take a snapshot. The automation creates a new item in a different board based on the information from the original item. This new item would be the snapshot you described.
The item’s are sorted by the Quarter and the 4 automations for the 4 quarters sort the holdover date to the appropriate column.
Now, mine is designed on a much smaller scale (like 10 - 20 items) so I am not sure how the increase in number of items will effect the automation duration.
Hope this helps a little,