Depending on how far you drive day to day it may not be worth the expense of upgrading your 240V circuit and buying a new EVSE. If you basically can recharge your Volt in 3-4 hours today and don't use any gas on your daily commute then you would be able to charge a Bolt in the same 3-4 hours using your current 16 amp charging setup. When you happen to travel longer distance than your usual commute it will take longer to recharge; even if it takes 19 hours to fully recharge the Bolt's battery using a 240V/16 amp charging setup you can complete the recharging of the Bolt's battery in two or three shorter sessions over a day or so rather than one long charging session.