Hi! I will be arriving in Bali on 31-Aug till 9-Sep. Spending first 5D4N diving in the Gilis before returning back to mainland for dives in Tulamben and Nusa Penida.
Not sure of your cold water tolerance, temperature in NP wld be approx 18 - 20 deg celc. Wear a thermal guard or double layer of wetsuit to keep you warm.
Good luck! It is the Mola-Mola season there. :)