Left Munich yesterday and the regular BA lounge is still open (I was amazed).
There is no food apart from some oranges, apples and the odd cereal bar. However, there is the usual complement of beer, soft drinks, wines and spirits. No one mentioned the lounge at check in (which is now in area B as they have shut check in at area A). Seems that C security is the only one open so you have to march to that, go through regular passport control afterwards (as the self serve gates are now for German passport holders only) and then walk back to the B departures which is only a couple of mins away.
For the one Munich departure the lounge was empty and I was the only BA passenger that went with the other 4 people on the QR flight to Doha.
FYI, there are still the usual outlets selling coffee, pretzels, beer etc outsde the lounge by the gates and you may want to take advantage of these given there is no food served on BA planes any more (save the shortbread we were offered in CE)