Yes escorts have a limited supply of depth charges. As for your main question, I can't help much but it does appear to have similarities with this post http://www.subsim.com/radioroom/showthread.php?t=189886 .
Nemo
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"I'm afraid there is no disguising the fact that King's obsession with the Pacific and the Battle of Washington cost us dear in the Battle of the Atlantic".
Sir John Slessor GCB, DSO, MC, DL
AOC-in-C Coastal Command RAF
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