If your landscape area is anywhere adjacent to the pool remolding area I would recommend not doing any planting until the pool work is done.
You may want to schedule the soil prep to begin before they apply the the final interior pool coating because if it becomes windy the compost can drift and potentially stain the finished plaster or pebbletec finish.

It's a delicate balance. This is where your project manager is invaluable.

The months of Sept, Oct. and November are some of the best months for planting in Northern California so long as the soil is not saturated from rain.
Frost damage should not be a problem so long as the plants are appropriate for your climate. If you chose plants that are borderline hardy for your area then I would wait until spring to plant.