That’s just information, nothing to worry about.
When using e.g caching of graphs, the binary formats can be incompatible between different versions. However the graphs settings are all compatible so far.
Now the question is, why have you downgraded? You do not seem to be using the latest version.
Is that so? I am using the version of pro that is on the asset store. I did go through some oddness when I tried to install the beta, ran into compiler problems because “Node” was no longer found, so I reverted.
It is possible there was some odd data from the free version still kicking around I guess? Or something got put back via reverting (from my svn repository).
EDIT: Just downloaded and tried reimporting the website version of pro, and the warning went away. thanks.