I think Apple _will_ budge for HEY

Apple so far has shown no mercy when it came to small companies, or even with big ones (see Adobe's Flash, RIP).

With HEY, Apple is again, picking on a small company, but probably the biggest one so far. Basecamp isn't Adobe.

Apple is also probably facing an upcoming EU investigation.

So far Apple had no reason whatsoever to acknowledge indie developers' needs (in that context). But HEY is different. With HEY, Apple has a chance to get a shit load of great PR for "showing mercy" for what is widely considered and comparatively speaking, a small company.

If they let HEY off the hook, they lose a buck or two, nothing that they're going to notice, BUT, get the PR they need for whatever's coming their way from the regulators, and a ton of developers, and some of the public.