Originally Posted by
genejockey
Stop, Swap, And Roll. Stop sign, top of the hill, before a climb, etc.
Alternatively, while coasting on a flat, straight, mostly empty stretch of road, hold the empty in one hand that's resting on the bars, and swap the rear bottle to the front. Then put the empty in the rear.
I've done that, but had a bit of a moment on Tuesday morning. Think I'll try to avoid it.