Is there a document describing the new features and changes to Square?

[fireworksking]

I noticed an issue where discounts are being applied differently than intended and I suspect something in the system has changed regarding item categories.  Is there a change log document available ?

[Candlestore]

@fireworksking ;

Square has now made Subcategories available and that might be the problem with the discounts?

But as far as I know there is no one document that lists all changes Square made or what has changed with a recent update.