[Twisell]

The Apple security paper describe how to disable ADP through a key rotation sequence.

This will be a "forced rotation", they just need to decide how to communicate to users and work out what happens to those who don't comply. Lockout until key rotation look like an option as someone said.

[biggc]

Naive question: what prevents Apple from pushing a malicious software update that automatically disables ADP to UK users?

[kbolino]

Yeah, this seems the most likely thing to happen here. You'll be forced to disable ADP to continue using iCloud in the UK. This still leaves the question of tourists and other visitors, but it at least fits within the parameters of the system without changing its fundamentals.