Not sure yet whether this qualifies as a bug. After installing the update Photoshop no longer looks in the following folder/package for printer ICC profiles:
This is on High Sierra 10.13 but it was the Photoshop upgrade that stopped my profiles being visible. The strange directory structure above is the only place on the Mac where the Epson P800 driver installs its ICC profiles, so I'm confident that the prior Photoshop CC searched it.
FYI I simply copied the contents of that package to the folder /Library/ColorSync/Profiles and all is well.
Can anyone verify that Photoshop should be searching everything in the /Library/Printers tree? Thanks in advance.
OK, looks like you have to install Epson driver v10 (Sept 2017), which also adds some extra options to your printing.