I didn't realise the below
('Entry requirements' page)
The Foreign, Commonwealth & Development Office (FCDO) advises against all but essential travel to Greece, except for the islands of Rhodes, Kos, Zakynthos, Corfu and Crete, based on the current assessment of COVID-19 risks.
So we could go as long as we can isolate for ten days on return and do all required tests.
Fingers crossed 