Hey Mychaela, as Neels pointed out, it's not only up to Osmocom.
None of us have any idea what might be the requirements to enter Germany by the time April comes around.
Please, let's not go any deeper into arguing covid or health/medical procedures on THIS list, AFAIK there's not a lot of virologists/epidemiologists/etc or even health practitioners (alternative or otherwise) on here.
Best wishes,
Keith.