fcm).deviceTokens in the requests always get added to the current list of the subscriber's deviceTokens (i.e. if the current deviceTokens is ["1","2","3"], sending a request with deviceTokens: ["4"] will make it deviceTokens: ["1","2","3","4"]), that part is actually well and good for me. (It might be worth mentioning that it conflicts with a solution that was provided on an older thread: How to remove deviceToken)deviceTokens array? I observed that updating with deviceTokens: [] indeed clears out all the deviceTokens. So I'm wondering if the current best way to delete specific tokens is clearing it out first to deviceTokens: [] then doing another update credentials request to set the filtered out deviceTokens? (2 requests)