Another variable in the mix that might be relevant is coaching vacancies.
The Yale director is retiring, there’s some question about what will happen at Dartmouth, and as far as I know BU hasn’t filled the director role yet.
That’s just at the two D1 conferences mentioned. Even if those programs aren’t of interest there can be a domino effect (as in: not out of the question that assistants at other programs might apply for the Yale job).
All of this can delay communications and decisions in some cases.
As far as D3 vs D1 timing, I think it’s safe to say that Ivies will look to fill their slots with target-level recruits first but that won’t necessarily shake out at all the programs until the fall. At the point where things start to fall into place, coaches will look further down the list. Some recruits that were on the fence between D3 and Ivies will get offered slots at that point, but maybe not to programs they’d prefer, or maybe not at all.
So yes, unfortunately a recruit like this might be in the position of needing to decide on a D3 offer before Ivies and Patriot league recruiting classes are finalized. As others have mentioned, if it comes to that an honest discussion with the coach(es) might be a good option.