on 3 may 1917, "bat" and the destroyer opened fire on the british submarine off blyth, northumberland. although one man was killed and a second was wounded, the submarine survived. in july 1917 "bat" was redeployed to the east coast convoy flotilla, this merging into the 7th destroyer flotilla based at the humber the next month, continuing in escort operations for east coast convoys. she would remain there for the remainder of the war.