GSX doesn't apply the A320 config to the A319 for sure.
And, I can only confirm the latest installer shows the A319, assuming it was installed in its default package folder, and it's activated in the Community when the FSDT installer runs.
What do you mean by "installed in its default package folder", installed in it's default location path? If it's what you mean, then the answer is yes, all my aircrafts are installed in the default community folder with the installer provided by the developer.
Regarding the FSDT installer i've download it the 28th of AUG, so i guess it's the last one, version 1.1.8
The last thing I did was unstalling gsx pro, removing %APPDATA%\VIRTUALI\PackagesCache and re-install GSX.
I'm still have only the A320 in option, while i also have PMDG737/777 installed (both in the community folder). Before doing this seated pax was working on those aircrafts, i didn't try since i did a new re-install.
I'm a bit lost and don't realy know what to do next.