Polaris Lounge Access for LH

Flying business class via Lufthansa and I know I can access Polaris Lounge but I saw this note from Lufthansa site:

*** Opening times may vary. In general, the lounge will open no later than 2 hours before the Lufthansa Group flight. ***

Does it mean I can only enter the lounge 2 hours before the flight?

Edit: Flying SFO to MUC