No, they should still have 2 reds and 2 whites on board; the new wines have already been introduced in BE this month and they have been having the 2 reds and 2 whites so far this month - they shouldn't be switching to only 1 red 1 white next month.

The difference between the new wine offerings now and before is that people will no longer be confused or disappointed because they saw a selection of 3-4 reds or 3-4 whites in the menu and expected all of them to be offered on the flight.