FYI I've got the app installed from the Google Play store, and it shows the same version as GitHub:
Proton
Empowering you to choose a better internet where privacy is the default. Protect yourself online with Proton Mail, Proton VPN, Proton Calendar, Proton Drive. Proton Pass and SimpleLogin.
Proton Mail is the world's largest secure email provider. Swiss, end-to-end encrypted, private, and free.
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Proton Calendar is the world's first end-to-end encrypted calendar that allows you to keep your life private.
Proton Drive is a free end-to-end encrypted cloud storage that allows you to securely backup and share your files. It's open source, publicly audited, and Swiss-based.
Proton Pass Proton Pass is a free and open-source password manager which brings a higher level of security with rigorous end-to-end encryption of all data (including usernames, URLs, notes, and more) and email alias support.
SimpleLogin lets you send and receive emails anonymously via easily-generated unique email aliases.
Well, normally, you could assume that the Releases on GitHub might be a little newer than on various app stores because Google Play and the Apple App Stores have annoying approval processes (and optional delayed rollout strategies) but the fact that the GitHub Release is behind what they have published in the app stores is concerning...
I don't know the answer to your question (though I'n guessing their github isn't the repo they actually use for development and thus could be a little behind), but Aurora and Google Play should have the same version, as Aurora just fetches it from Aurora as far as I know.