Zeeky, ime it depends pretty much on how quickly your supply settles down, and how readily your baby takes to BFing, and how easy you are finding it feeding this time around. If you are having latching issues and introduce a bottle too soon, then the baby might see that as the easy option and it might make those latching issues worse.
Similarly if you are having supply issues then there is a chance that the expressing will interfere with this, if you don't make sure you replace the feed you miss with an expressed feed, which means that you would need to be up expressing so you might as well just BF!
And as others have pointed out, it depends entirely on the baby. My DS2 wouldn't entertain bottles at all, but DD before him didn't care where the milk was coming from as long as it was coming. DS2 has been getting a cup since he was about five months old, and even then it was only under extreme circumstances that he would entertain it....he much prefered to wait until I was back from wherever I was to get it direct from the source!
It's my feeling though (as a peer supporter) that two weeks is probably too early to start missing a feed to get an earlyish night, as your supply is still settling down at that point, however depending on how things are going, four to six weeks might be a better time to think about it. I would suggest getting a local BFing counsellor on board who you can turn to readily for help and advice should you need it and to wait and see how this baby is and how things go.
forevermore, its not exactly "nipple confusion propaganda "; it does exist! And while there are lots of babies for whom it isn't an issue (my DD was one of them), there are just as many, if not more, for whom it is. Just as there are lots of women who successfully combine breast and bottle feeding, equally there are lots of women for whom mixed feeding is the beginning of the end of BFing.