Read the options agreement or whatever mechanism was used (or have an attorney read it). Sometimes there’s language in there that allows the company to buy back options you exercised at current valuation all the way up to ipo.

Do you know if that applies to common stock as well, vs options?

I would actually love for the company to buy the stock back at the current valuation, that'd be the closest anybody will get in a while to seeing a payoff. I also know the company doesn't have anywhere close to the amount of funds necessary to do that though. And if that happens at later rounds with a higher valuation, that's fantastic.

There’s no single answer for all companies, just what’s typical for boilerplate incorporation documents, and an entity with an options agreement is already past that point. Reading the company’s options agreement and its Articles of Incorporation and Bylaws (for restrictions on share transfers, right of repurchase, etc.) is the only way to answer your question.