Musescore portable vs Musescore PortableApps

I'm a regular user of Musescore and currently run version 3.5.2 via the PortableApps platform. I know though that version 3.6.x has been released and is apparently a significant upgrade in terms of appearance. I know also that the good folk at PortableApps will provide an updated version via the platform in the fullness of time, assuming this is still technically possible.
In the meantime, I decided to download the portable version from the Musescore web site i.e. from the developers. I was surprised to find the downloaded file has the .paf.exe extension and would therefore appear to be a PortableApps release.
I undertsand that applications packaged by PortableApps.com follow strict guidelines and not all portable applications produced by developers/publishers adhere to these guidelines. So I'm wondering why the portable version of Musescore from the the Musescroe web site is in PortableApps format but not available through the normal PortableApps platform update process?

Thanks for any information you can provide.
Paul vP