While life is taking time with new job, family etc. Sporadically i've some time to cover-up some old things.
Re-reading some of my notes and collections of data, i found one episode we briefly convered but it's not detailed in Arctic:
20 March 1945 in Arctic.
Depth charges launched against sub U-997 by Soviet guard boat "Smerch", causing light damage.
I read/know she had support of "BO" /submarine chasers. It is known their identity? (could be interesting to know if they were project122, or it was a use for the lend-leased allied boats).