Pumping tips?

My baby is almost 3 weeks and I’m starting to notice a bit of a pattern to when she wants to feed.

(Roughly) Between 6am and 12pm she cluster feeds and seems to want my breast every 0.5-1.5 hours. From 12pm she might take a feed about lunch time and have a good 4 maybe 4.5 hour sleep. Then from about 5pm to 11pm she cluster feeds again then from 11pm to 6am she might wake twice.

I like to try and pump a bottles worth per day to freeze for when we go out (so ideally like to express about 3oz)

After her first morning feed my breasts don’t feel quite empty so I feel like this would be a good time to pump but because she could wake so soon for a further feed I don’t know if this would be worthwhile or not

Any advice from anyone else in a similar position where baby doesn’t feed 3 hourly?