Game description from the designer:
Simple/abstracted. 9 seasonal turns, Spr42-Spr44. Hidden task force movement until recon/contact. Destroyer divisions (4 ships) and individual warships of higher classes, from Koeln to Tirpitz for the Germans and Scylla to Alabama (to Victorious) for the Allies. 8 of 12 freighter loads must make it to Murmansk and/or Arkhangelsk per season - more than 1 convoy may be necessary. Loss of a capital ship can alter season victory outcome.
Could be multi-player game, and - as for my Malta convoys game Lion's Lair - surface battles could be resolved by miniatures instead of the boardgame's rules/mechanics.
Each season can take from 30-75 minutes, because of point by point possible U-boat attacks - let alone the Wolfpack - so the campaign game is much longer than Lion's Lair.