Hi,
congratulations on your new baby!
First question has got to be, can't you just keep bf your baby, if DH is there and taking care of her? Kind of, brings her to you whenever she needs a feed. Or change to a every-four-hours schedule or every-six-hours-during the day and more in the night.
If that not possible (although employers should provide options!) I'd say definitely keep bf at night and whenever you can, with a particular emphasis on at least one feed and/or expressing between 2 and 5 am. Is a bother, but seriously does help keep supply up.
BM will keep in the fridge for up to 5 days I think. Always store it at the back of the fridge where the temperature is more constant/colder.
Good to know also would be that if it is only you who uses the pump, you don't have to sterilise it between every use. Once per day should suffice. We used to take a microwave steriliser with us when we went away overnight, microwaves are available nearly everywhere.
Seriously, experiment with expressing and with bottle feeding ahead of time. Or else you may be in for a nasty surprise if your DD decides she doesn't like the bottle. Or if you find it hard to express any significant amounts.
We had to bottle feed our DS after every (unsuccessful) breastfeed as he kept losing weight and was too weak to bf properly, and accordingly my supply had been dropping too. But we successfully got back to EBF later on, so it is possible.
Perhaps you can find a workable schedule, involving only one bottle feed (or perhaps two) per day (i.e. per working hours)? You BF immediately before starting work, and immediately after finishing, and your DD gets used to mainly night-time feeding? If you get that schedule established beforehand, you shouldn't have any boob problems either as they would already be adapted to it. If established beforehand, you can now even choose if you'd rather express while at work (at the time DD gets her bottle feed) or if you'd rather express between feeds in the evenings/at night when DD doesn't feed.
Though admittedly some babies won't be coerced into parent-suitable schedules!
hth