That already happened once with OpenSSL 1.1 which also wasn’t really backwards compatible.
It was messy then, it will be messy now, though when you took the 1.1 opportunity to modernize your code to current best-practice as requested by the library rather than just fixing the minimum, you might be pretty ok this time around
You know, I think it was a deep memory of the switch off of 0.9.8 that gave me the initial thought without realizing. Maybe the older programs will be more prepared after all. Although I hope they weren't expecting a single-digit increment..
It was messy then, it will be messy now, though when you took the 1.1 opportunity to modernize your code to current best-practice as requested by the library rather than just fixing the minimum, you might be pretty ok this time around