Does your heater have any TOU controls ?
No, wish it did. Hoping they will add a firmware update some day...We have one of the latest Rheem 65 gallon units. For about $49 we added a WiFi module (EcoNet) that lets you adjust some of the settings that you can right on the water heater like on/off, temperature, mode (heat pump only, hybrid, electric resistance only, etc), vacation mode, etc...
EcoNet 2.0 software just installed today on my iPhone with TOU controls. Looks like we now have the ability. I have the water heater set now only to act as a thermal battery and run the heat pump during lowest TOU timeframes.
'19 Model 3 SR+ (own), '19 Leaf SV (leased), '12 Plug-in Prius (sold 3/19), '16 Leaf SV (prior lease), 11.43kW Solar PV (16MWh/yr real production), 20.5 SEER/13.0 HSPF ducted air-source heat pump, 3.70 UEF heat pump water heater, Induction Cooktop