Someone with a 2019 Volt with the 7.2kW charger pulled charging data, graphs from their Juicebox Level 2 EVSE:
https://old.reddit.com/r/volt/comments/a7mmc3/2019_volt_72_kw_charging_graph/
https://old.reddit.com/r/volt/comments/a7mmc3/2019_volt_72_kw_charging_graph/