I don't know if all of this makes sense to you but it's like the same concept of the Outro to Mt St Helens, where ended up back in the key if G.
that wasn't a half step change, that was a minor 3rd change from Bb back to G. the reason it had ended up in Bb was NOT because i ever wanted to 'go up a minor third.' the bridge just goes where it goes. it's a getaway bridge. (actually even the lyrics are about getting away, at that point). and actually, according to the rest of the song, you would expect to pop back to G BEFORE the start of the verse, which is what it does the previous time. but it actually didn't seem to work there, so i ended up staying on Bb for the start of that verse. and then pivoting on 'crazy' back