Sorry if this is a silly question
No questions are silly. Please don't apologise for asking.
Rather than thinking about how long you should shush/pat in the night though I'd be thinking more in terms of getting her fed rather than trying to put it off.
The examples you've given show that she can sleep a lovely long stretch some nights and that's great. She is still very young though and depending what she has done in the day, when she fed, how much energy she used up (in play or crying or in developmental milestones) or if she is having a growth spurt then she might be hungry sooner in the night. I can understand the 10pm soothing back to sleep as it had probably only been about 2hrs since the BT feed and if she went off quite quickly with soothing then my guess is she probably wasn't hungry. By 1am though it has been a long stretch since the last feed at BT, 5hrs or so, which is classed as "sleeping through the night" so I think rather than spending lots of time trying to resettle I would have suggested feeding right away. One possible reason for not taking a full feed could be that she was just too tired by that point having been awake for an hour and perhaps crying or fussing for an hour and so just took what she needed to tide her over and went back off to sleep.
3:30am at which point I feed (breast+bottle) and put down again, often not needing any additional soothing so possibly too drowsy?
If she can be put down and not need additional soothing that's fine.
It's not always easy to know in just one or two nights if LO is waking at a different time for a reason or what the reason is but I'd suggest if it's been 3-4hrs since the last feed then it's okay to go ahead with a feed and get everyone back to bed as quickly as you can.