I am lucky enough to be in Greece with return planned for 17/7. In light of rumour that govt is going to change self-isolation requirements from 19/7 I’m considering changing flights home.

I know I can make new one-way reservation and cancel this for an FTV if I stick to original dates, but can I get return leg of my original (Avios) booking converted to FTV if it I don’t use it?

just to be clear, I ideally intend to hold both flights until decision is known.