How to replace a copper fitting close to another fitting

Sorry for the duplicate post. I posted this in the remodel forum when I should have posted in plumbing.

I am working on a basement finish and I have just completed installing ¾ inch hot and cold copper supply lines for a new bathroom. I installed shutoffs before putting in the supply lines. I just turned on the water to pressurize the lines and I have 1 leak. There is a 90 degree elbow about 1 inch from the shut off in the hot supply line. The joint in the fitting on the shut-off side is the leaker. So now I think I need to:
1) drain the lines
2) heat up that fitting and take it apart
3) clean the pipe up, removing all of the old solder
4) re-solder in a new fitting

My question is will I compromise the soldered joint in the shutoff (that is only one inch away) when I heat and take apart the fitting I need to replace? Are there any steps I can take to protect the nearby soldered joint before heating up the one I need to take apart? I am an amateur and I have never taken apart a soldered fitting before. Any advice would be appreciated.

Thanks, Jack

Heating are reheating is fine.

You can put a damp rag on the part that is done too.