The wise thing is to not offer perpetual licenses in the first place. You can’t predict the state of your business in 10 years let alone beyond that. Why make commitments that? Marketing of course. So if they’re going to raise capital that way (by one-time revenue from sales of perpetual licenses) then they can’t just decide that perpetual doesn’t mean perpetual anymore. All in all this will come down to a legal duel between expensive legal teams.
“unrealized gains” that you can somehow live off of indefinitely.