Bad idea: Stopping behind commercial vehicles at a junction.
Why? Because said commercial vehicle may unexpectedly reverse, despite huge blind spot that could easily hide a small car, let alone a cyclist.
Despite sound of cyclist being struck by back of van, Mr van driver may continue reversing until cyclist drags them self off the floor just before going under the rear wheels, and banging on the side of van.
Lesson learned this morning: Stay out of the blind spots, even if there is no possible reason for the vehicle to need to reverse.