How do subscription offer codes work for existing customers?

Say I have a customer with an active one-year subscription and want to create an offer code for 6 months at a reduced price that's available to all subscribers -- new, existing, and lapsed. If my customer with an active subscription uses the code, will the promotional period just occur at the end of their current active subscription period? I can't find this documented anywhere -- a link would be much appreciated.

Correct, if the offer code is for the same product that the customer is already subscribed to, then it will go into effect at their next renewal event.

How do subscription offer codes work for existing customers?
 
 
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