Unnecessary rollback for a hidden node after a priority takeover reconfig

Hi, I have a P/S/H(priority 2/1/0) replset using 3.2.9 with replicaton protocal v1. And I noticed that during a reconfiging to (1/2/0) procedure, the Hidden node entered rollback state because he choosed the original Primary as his new sync source after the new election, which soon rollbacked too because he is no longer the Primary. This Hidden entered rollback because he has a higer term(the latest right term synced from the new Primary) than the sync source(the original Primary). But I think this rollback is unnecessary. Is this a sync source choosen bug? I have all the 3 nodes' mongod.log if you need. Thanks!