I am not sure whether I have updated this, but it appears that OW has moved about more than an hour away from where we live (and H's office, as his work is close to us). This means that H will have to go through a lot of commute going back and forth. Because he does not want to drive, he ends up taking the train or cycling.
I do not doubt that OW is doing this to get him away from me and son, but all he ever says is that "she is moving away because she was moving on with her life and too hurt to know he came back to me that time." I really do not get how an intelligent adult can't see that this move is problematic.
Either way, H has been OK enough in communicating about son and what son has been doing during isolation. I have been responding in short and nice way.
Their isolation period will end on Thursday so we will see how it goes. Fingers crossed.