Telling HR About Major Change

I'm in a "hard" STEM major right now and that's what's listed on my resumé. I used to be majoring in something less technical that has a small amount of coursework overlap / credit duplication with my current major.

Because of this, I'm only receiving half credit for one of my classes right now (2 units instead of 4). I'm supposed to graduate in less than a month-and-a-half, but because this half-credit situation, I'm going to have 2 fewer units than I need to graduate with the technical degree. I'll have completed all of the necessary classes, I just won't have the units, and my university doesn't make exceptions for this policy.

The only way for me to finish the major I'm in now would be to wait around for another year just to take one specific class that's offered in Spring. Alternatively, I could graduate in 6 weeks with the less technical degree.

I'm in the running for a couple of different positions. I've met with a bunch of the teams' members and I'm really hopeful I'll end up getting an offer at one of these firms.

Anyone have any advice on when / how to tell my recruiters? I don't want to go through the processes, get an offer, and then have them rescind it because they thought I was lying to them about my background, but I also don't want to be a problem child right now and give them any reason to prefer another candidate over me. I think it's probably best if I tell them sooner rather than later, but I'm open to other perspectives.