Had one ice field in HS that has had nothing since the update then a field spawned yesterday, so looks like random spawning could means days between spawning in some systems.
Mining ice can be therapeutic if you’re tired, but it’s generally hopelessly boring. My home system used to have ice every 4 hours. I noticed an ice belt for the first time in 3 days yesterday. Citadel fuel will become very expensive. Between the fuel price and those annoying cores, CCP is trying to make stations harder to own.