[picofarad]

Dont use a random IP to host? I use fastmail, even though they're trying to convince me that I need to pay ~$45 now instead of $5/year.

And they sent me an email explaining how grateful I should be, that I'm grandfathered in to being able to use my own domain on a "plan" they dont even offer., in a plan that didn't offer custom domains.

Well how'd I get all that then? I signed up for fastmail explicitly because $5/yr for custom domains.

Anyhow if you pay a host you're probably fine. Or find someone with an old /24 thats had a /31 or /32 unused for a long while, and no other black marks against the /24. And use that IP, set up demarc and all the other new email DNS stuff.