uSplit - UART Splitter for VESC-based ESCs

okay so i’m still waiting on parts, one being my battery, but in the meantime i want to upgrade all my little gadgets.

I have a Usplit from @Ricco (uart splitter) and want to upgrade it to the latest FW, i read the instructions but one thing i am unclear about is this


So remove power by unplugging the usb port or do i need to have it connected to the ESC and turn the power of my board off?
Cheers