People are often a lot more upset when they pay money and there is no exit plan. Shut downs can be abrupt and chaotic, suggesting they monetize immediately doesn't seem helpful either. If that's the suggestion, I'd ask: how much would you pay and how long do you expect notification in advance of a shut down? Do you expect a refund? Full or partial? Do you expect portability? If so, what kind.

$1/trigger/mo. 30 days. No refund if services were delivered, if I pre-paid then pro-rated refund. No expectation of portability.