To shape, you can prune any time you want. To encourage flowering is another matter entirely.

Hello, Frank. For the sake of safety and aesthetics, I would prune those stems that are bent against the curb all the way down. However, this may trigger new growth now and thus, I would time the pruning after the plant has gone dormant and the leaves & flower have dried out and turned brown.

Hydrangea arborescens (aka Smooth Hydrangeas or Annabelle-like Hydrangeas) and Hydrangea paniculatas (aka Pee Gee Hydrangeas) can be safely deadheaded or pruned now as they do not produce 2022 flower buds now but the other types probably have developed invisible spring 2022 flower buds by now at the ends of the stems.