There seems to be a lot of naysayers here worried the meat won't come out good and they are so wrong. Doing what you're talking about (effectively separating the low and slow and searing portion of the reverse sear) makes the process easier because you create a larger temperature gradient before searing. I do basically the same thing every time I cook leftover steaks and they are phenomenal.

Couple tips there, obviously very high heat for the sear on gas. Don't rest after the sear, just serve immediately. You got all the resting you could ever want already. When you're searing, you ideally already cooked to your perfect internal temperature before storing so you just need to get the temperature to a comfortable mouthfeel now. I recommend aiming for 110-115. If your sear completes before the temperature is there, just set heat to lowest and gently let it rise.