Which singles are unique mixes, different edits and new recordings (vs LP)?

[All Summer Long]

I can’t speak to a lot of these, but the single version of California Saga: California is faster and has some more vocals from Brian. It also has horn overdubs, and there might be other changes I can’t remember at the moment.

[RingoStarr39]

There's an alternate single mix of School Day that was also on Ten Years of Harmony.

https://youtu.be/FLUxw62eCNA

[smile-holland]

Bluebirds Over The Mountain:
The Dutch mis-mix was already mentioned by dogear. They acccidentally mixed the extra percussion for the single version up front instead of more in the background). Surprisingly despite of this it still was a decent hit here.

Surfin’ Safari:
Also mentioned by dogear. Original 60s German release on the Ariola label. But it’s a different take they used.

And if the Party tracks that were put on single fall under this category:
Mountain Of Love: no intro/less chatter after (b-side Then I Kissed Her, released in most countries in 1967)