Is Royal Canin cat food "Urinary SO 33" the same as "Urinary SO"? I can't find any solid information on what the difference between them might be, or if it's just a re-branding. Urinary SO 33 is still for sale in some places (note name on the package in the picture).
I reached out to Royal Canin on Twitter. While this isn't a verified account, it is the account that Royal Canin lists on their webpage, so it should be trustworthy and written by someone from the company.
The representative said
This is simply just a package change. You will only see it labeled as Urinary SO now.