I would think at 9wks it is still very normal to be feeding once in the night - particularly if you're not doing the df. Tracy suggests by 4mths they no longer need a feed in the night but to have the DF and then drop the df around 7-8mths. So it would be normal to have a night feed up until that time if you're not DFing. However, if the time of wake up in the night is fluctuating it will generally be hunger. If the time is regularly the same, you can try resettling without feeding (ie pat/shsh) if you wish. If you use a dummy, you could try using that as well. I am still feeding my dd in the night at 6mths (we don't df). The other method you could try is to offer less in the bottle and see if that helps reduce the overnight amount, but up the day bottles slightly.
As far as waking up grumpy, do you keep things quite low key for a wee while to let her adjust - maybe hang out in her room and just talk to her. Also, if it takes 15min for her to adjust, there's no problem if you're not feeding on the designated hour, but 15mins later isn't going to affect your routine too much.
HTH