It wants me to uninstall and reinstall since the signature of different, which makes sense as it from a different source, but it doesn't mention anything in the changelog.
Jerboa is provided by both repositories. Izzy's pushed the update before F-Droid's is all. You can switch to Izzy's or wait or DL the apk from GitHub but signatures are different for all three.
Do you know why the signatures would be different? At my company we release our app on Google play, galaxy and Amazon store and I'm pretty sure we use the same signing key for each