Have been bfing dd for 2.3 years. Right breast has always produced more - when I used to express I could get 12oz out of the right one and only about 4oz from the left. dd has always fed happily from them both and at 2.3 is no down to both sides, morning, before nap and before bed.
I have never been away from dd for longer than 12 hours so never gone that long between feeds. DH and I went to a wedding last night and stayed away so dd didn't feed for 24 hours. When she fed this afternoon she fed on the right (or 'big one' as she calls it ) and it took a while but she I did feel a good let-down and she was really happy. She then went to feed on 'baby one' - the left and hung in there sucking for 10 mins with no let-down! she finally got fed up and said 'baby one milk is finished'! .
So I guess I'll have to see what it's like in the morning and if the left one has given up I guess I'll be feeding one sided as dd has no intentions to give up - it took her approx 3 mins on returning from my mum's today to tell me she wanted to feed!