“They were extremely fast , very deep diving and caused many a sleepless night for our sonar men. It would always be a good idea to know exactly where the Alpha boats were at any given time.”
When I was at sea in the 80s, there was a sitrep broadcast every 6 hours with the precise position of every Soviet sub in their fleet. If one was unaccounted for, a general alert went out to the entire fleet to be on the “lookout”.