Originally Posted by TWA884

Enrollment on Arrival is available to everyone who received conditional approval.

The enrollment interview must take place within 365 days of receiving the conditional approval; there is no need to schedule one if you intend to do EOA, but it is not a bad idea to schedule an interview as a back up plan.

As long as you update your address during the interview, I don't foresee a problem; I assume that a UK citizen qualifies for GE regardless of their country of residence. Please refer to the "Global Entry Procedures and Timelines of Applications and Renewal for UK citizens" and "Global Entry application - how do I change/update information?" threads for additional information on these points.