Could the Kriegsmarine still train in the Baltic?

How could the Kriegsmarine train in the Baltic if Britain operated from Norway?

It probably could not train there safely; the Baltic would become contested by British aircraft, submarines, and coastal forces.

The Baltic becomes contested by British Beaufighters, torpedo aircraft, submarines, and fast coastal forces operating through Scandinavian waters. Under those conditions, the Kriegsmarine could no longer treat it as a secure training area. Neither side necessarily gains full control, but Germany loses the protected space needed for routine work-up. British forces can threaten the area from Norway while Germany is already short of ships and bases.