I emailed Epson, asking about a printer driver for Big Sur. Their reply (and a heads-up for any Epson owners):

Thank you for contacting Epson regarding your Epson SureColor P600. In reviewing your incident, it appears that you have opened one of our online knowledge base articles to help you in resolving this issue.

In response to your concern, please be advised that currently, there's no available Epson printer driver for your product for MAC 11.0 and we do not have the exact details to when it will be available.


Jon

macOS 11.7.10, iMac Retina 5K 27-inch, late 2014, 3.5 GHz Intel Core i5, 1 TB fusion drive, 16 GB RAM, Epson SureColor P600, Photoshop CC, Lightroom CC, MS Office 365