ANSWER:

If you take off the first pair while you are still in the state of the original wudhu which you washed your feet in, wearing another pair won’t affect wiping on that the next time you do wudhu. 

If for a wadu I do masah on socks, and later take off socks or change socks (while still in state of wadu) is my wadu still valid? Or do I perform wadu again