If the time for wiping over the Khuff has ended, and you have Wudu, then your Wudu does not become invalidated according to the correct view. If a person takes off the Khuff or socks after wiping over them, his Wudu does not become invalidated according to the correct scholarly opinion.

You can do wudu with socks on if the socks have been put on when you are in a state of purity and they are pure, and the wiping may be done within the time specified by Shari`ah.

The time for wiping over socks may expire but your Wudu remains valid as long as you do not perform any act that breaks it.

There is no evidence to indicate that taking off leather slippers or socks that have been wiped over invalidates Wudu. If you wish to wipe over the socks again after breaking Wudu, you must perform a complete wudu, including washing your feet, before putting the socks back on.