Signal version too old for importing backup on /e/

I want to switch an existing Signal backup from Galaxy S4 (LineageOS) that still had Google Play to /e/ on an Galaxy S7 Edge. This worked for every app yet except Signal: When importing the backup, I get an error that it’s not possible to import backups from a newer signal version.

Comparing the versions, I have 4.45.2 on the old S4 from Google Play but the new /e/ S7 Edge has only 4.43.8 from last month. The Homepage of Signal offers APK downloads, where the latest version is shown as 4.44.7. Couldn’t downlow exactly 4.45.2 by modifing its link.

It may work using the latest 4.44.7 but I really don’t want to install apks by hand without having them managed by some app store. This Smartphone is designed for my parents, which can’t handle manual apk downloads.

Would be like to know when apps in the store get updated. Regarding to this topic I found this thread which asks for the general app source. This is also important for me since it could be a security issues if e.g. old apps with known security vulnerabilitys are shared in an old version on /e/ app store. According to the linked thread, it seems that this is not transparent documented yet since the app store is new.

Sadly it’s not simple possible using another free app store like F-Droid since I couldn’t find Signal there.

Edit
Found APKPure where V4.45.2 is listed with 9th of august as release date. Seems a recent version. Google Play on the old Galaxy S4 shows that the last update was on 5th of august. Downloading 4.45.2 from there would be a workaround but as said this topic is more for the general question how this issue can be resolved permanently and ongoing using our app store and maybe also how updates were handled generally.