Sorry, not sure I understand your post- is this just for one day? You can express if you like but one day won't have any impact on your supply if you don't and you can catch up again the next day. It might be nice for him to have a familiar drink, will he take it from a sippy cup? I don't think you're making a massive deal out of wanting your DS to be happy while you're away from him
I'm going to be away from DS at the end of April, probably for 2 feeds (late afternoon & bedtime), but certainly bedtime anyway. He will be 11 months by then. He's never had milk from a bottle and I've not even bothered trying to express this time round (he's DC2).
He eats loads at mealtimes (blw) so may not be so reliant on bf for calories by then.
Is it worth worrying about the bedtime bf? He'll be put to bed by my MiL who he sees very regularly although she's not done bedtime yet.
I think I might be making a massive deal out of this...DH seems to think so anyway