Can I delete a subscription rule and keep my subscriptions active?

You can safely delete subscription rules. Your existing subscriptions will remain in the app and will still function the way they did before. If you are removing recurring invoice subscription rules, then just keep in mind that the only thing that the recurring invoice subscription rules can control directly are the invoice schedules (for example, if you set the recurring invoices subscription rule to send emails with payment links at a specific hour or a specific day of the month or week). When you delete the recurring invoice subscription rules, only this part of subscriptions will be affected, which means that the schedule will fall back to the default schedule.