Method to support synchronous replication failover

A system to support synchronous replication failover for a storage system including a source site and a target site, the system comprising:

• a memory comprising computer-executable instructions;
• and
• a processor operable by a storage system, the processor executing the computer-executable instructions, the computer-executable instructions when executed by the processor cause the processor to perform operations comprising:
• locating a recovery snap set on the source site, the source site identified as a subject of a failover event, the recovery snap set comprising a snap set that contains a subset of data content that is also stored at the target site, and has a time of creation that is equal to or greater than a timeout value for serving input/outputs (IOs) to the target site;
• and
• sending a difference between volumes of the source site and the recovery snap set to the target site, the difference configured to enable in sync status between the source site and the target site.