Categories Month formatting

I have a date column and have turned on categories and sorting by year-month. It groups them nicely as you can see in the photo

My question is, is it possible to change the month label? When I select the cell and go to cell data format I see this

Nothing I change it to sticks. I tried to change it to month only, I tried number month only, I even created a custom type that uses the Japanese formatting 1月２３年 but all formatting resets to the January 2023 formatting when I click off and back on the cell.

The other category cells can be formatted in a style of my own choice, so I assumed the date category cell could be as well. But so far it doesn't seem like it.

This isn't a major issue, but it would be nice if I could. I'd like to get rid of the year (seems pointless when I am also using the year category, as you can see in photo 1) and shorten the month to 3 letters. Like in this photo

If anyone knows any way to do this, thank you!