thanks, I wish I had properly gotten the game to pause right away so it's not such a jarring start, as you do lose the bounce fairly quickly once you stop jumping with good timing. The decision to have you stop bouncing felt like a necessity to truly do something with the "don't stop" theme - if I had had time to put together a tutorial that explains you can restart bouncing by dropping to a lower level, that probably would've helped people since I'm getting the impression that wasn't intuitive to some people.
Once running, though, I think the timing window is fairly generous on the way towards an impact at a quarter second long (15 frames at 60fps), though to make the automatic bouncing feel correct there isn't as much of a window once you've landed (I believe it's at ~2 frames). If your internal sense of timing is to press jump right after you land then it will continually feel wrong, though. Not much I can do about that except I did put in the option to have the game handle all that for you and the option to play at a slower speed if it was too difficult. Truthfully I have no idea how one could execute it any better, though it probably wouldn't hurt to include a third difficulty/accessibility option to make the input buffer window even wider (or smaller if people wanted more of a challenge).