Really hard to say without knowing what they have on there. I think you may also need some specialized primer. If they used something like Thomason’s Water Seal, even that might be a crap shoot.
You could always do a test with a sample size amount of paint.
You could talk to the folks at a specialty paint store.
I would post this question over at house-improvements.com. There are a few general contractor types who have run into a lot of odd-ball situations.
If you are sanding in an older house, I would test for lead.