Three weeks notice is rough and you should treat that as a lesson in contract terms rather than bad luck. Things worth pushing for: a defined renewal window with notice measured in months not weeks, first right of renewal at a capped rate increase, and a wind down period long enough to renumber without customers noticing. Longer initial terms usually get you better rates anyway. We negotiate terms on our leases with InterLIR Global
https://interlir.global/ , and multi year commitments made the renewal conversation much less tense. Also keep a renumbering runbook current. The protection you control is being able to move fast when you have to. And keep customer facing IPs off documentation you cannot change quickly, that is what made our last move so visible.