No, I don't have a dock. I have two external hard drives connected to the USB-C ports - one for TimeMachine and one for CCC backups. I left them connected during the upgrade. Not sure I understand the meaning of your question.
It was more of a rhetorical question and statement. So you're having a problem with the upgrade without even the variable of a USB-C dock? Now I feel even worse about upgrading my own machine...