Do I need to give advance notice of my expected traffic levels?

No. Aculab Cloud scales dynamically in response to demand, so we don't normally need advance notice of your traffic levels. Of course, it will help to know in advance if you expect traffic levels to increase substantially, for example when an unusually large major campaign is scheduled to run. In these cases, a few days' notice of the likely traffic patterns is required. That allows us time to provision additional PSTN capacity if required.