Is it just 2 weeks you'll have to pump for?? If so I'd say you'll be fine.
By 9 months your supply should be well established- if you're cutting down from 4 feeds or so a day you might get a bit engorged as you adjust but that should settle and a daily pump should ensure you have supply at lunchtime for a feed.
I went back to work when my baby was 10.5 months- full time, shifts. She was feeding every 4 hours or so in the day, but refusing bottles/cups of milk or formula so I never bothered expressing (had a freezer full of frozen milk that I had advance pumped in preparation that all went to waste!). I fed on demand when we were together and my supply easily adapted, it's so well established at that stage. I needed to hand express in the daytime in the beginning, and still do on the first few night shifts of a week. So if you want to pump to give the milk- absolutely go ahead. If it's just to keep up supply, I wouldn't worry.