When starting spacemacs I was getting the following errors:
Package php-auto-yasnippets is unavailable. Is the package name misspelled?
Package phpcbf is unavailable. Is the package name misspelled?
It's discussed here: https://github.com/syl20bnr/spacemacs/issues/14381
They seem to have been removed from Melpa.
I can stop the errors by adding the package names to
dotspacemacs-excluded-packages in .spacemacs.
I don't know if it will cause any problems with PHP - we'll see. Someone there suggests moving to lsp backend for PHP - I could try that at some point.