It wouldn’t be that unusual. Remember they use to use the 767 to lots of European cities. 787s have also been used on flights to ZRH, ATH, LCA, STR, MAD, AMS during lockdowns (mainly for cargo but shows they have no issue if there’s money to be made).
It would also help keep the crew regular on the planes which can be important. If you’re going to do training flights why not earn some money at the same time.