hello N3k0-san
yes, the GOG version is 1.6.659.0.8 with SKSE 2.2.2
The release on GOG was a bit later, hence the newer version of the creator.
The version on Steam is based on the older Skyrim version before the current Skyrim/Aniversary patch,
something like this happens because the Enderal SE version does not come directly from SureAI,
but from an external creator from the community and we only took over the release on Steam.
(SureAI no longer takes care of any updates there, as our developers focus on newer games)
The actual creator
of this SE version has offered newer patches on his own site as a standalone mod version,
but the version there is not as simple as via Steam, but like a big mod.