I've just made a gorgeous quiche lorraine. same recipe I always use, with pancetta, gruyerre and creme fraiche. Tasted the mixture, thought it was a little different but not unpleasant.
Just chucked the empty pot in the bin and noticed to my horror that the use by date was July 14th. And it had been slightly opened. And it said on the pot not to exceed the use by date. 
Have I got to chuck the whole thing away? WIll it make me puke all night if I eat it?
Obviously need to check the contents of the fridge a bit more thoroughly. 