Increase exposure of multiple frames by 1

Hi.

I have a layer with frames that are being held for variable exposure rates. It’s a mix of 2’s, 3’s and 4’s.

Is there a way for me to increase the exposure of all these frames by 1, so that the 2’s become 3’s. the 3’s become 4’s, and the 4’s become 5’s and so on.

“Set Exposure…” simply evens out all the frames to the same exposure, and kills my established timing, which is not what I want. right now the only way for me to do this is to rapidly tap “increase exposure” and “go to next drawing” shortcuts and run through the entire timeline like so. It would feel more optimal to be able to select all of the frames, and just click “increase exposure” once, but doing this right now just increases the exposure of one frame.

Any solutions? Couldn’t find one from the forums or the tutorials