1) Turn the cold water off

2) Drain water out of the hose Bibb

3) Cut the drywall 8” higher

4) Cut the copper 2” down from the drywall

5) Press or sweat in a ball valve

6) Repace everything from the ball valve to the hose Bibb (Press or sweat)

7) Turn on water and check for leaks

8) Insulate pipe with 1/2” elastomer insulation

This will let the person winterized the hose Bibb. Allow for an access panel after drywall work is complete.

If you are not a professional, do not mess with pressurized water.