People have asked for this many times. For example if you accidentally skip forward or just want to add one more interval. I have another idea, that I think is a good one
It’s repeat interval but it shows a popup that defaults to your last interval and rest you did but allows you to modify it and add multiple new intervals.
This is just an idea at this point. Trying to make it as simple and fast and flexible as possible. In most cases it could be just 2 clicks to add 1 more interval like you just did.