Stripe does not natively support pausing a subscription. You can, however, cancel the current subscription and request the user to subscribe when he is ready.
Stripe doesn’t support the minimum number of payments before cancel option. By default, cancelling a subscription is done by the site admin (you). So if you have communicated with your customers (using terms and conditions) that the minimum number of payments is 3 before a subscription can be cancelled; then you can explain the situation to them when they contact you to cancel.