So why did you replace your boots?
Last season I rode some s/m 390 Bosses with size 10 DC boots. DC makes some small boots so they are more like 9.5s, but they still worked. This was not an ideal set-up and I was hugely underwhelmed by the 390s. For this season, I decided to replace my 390 because I felt they were the bigger problem and I wanted to try out different bindings.
You could do what I did and sell the 390s and put that money towards your new bindings if you go that route.