[BLK18]

I'm looking up TSBs and sometimes they have a sample illustration of the engine code info sticker on top of the cam cover. The problem is the only ones I can find only explain what "Item 1" is, which is the engine part number. Excluding Item 5, which I know that's the engine size), does anyone know what the remaining 2 through 6 items mean including the 227 at the top-right corner? (and for Item 1, what does the CX and AA mean? The TSB says the 184 is the engine base number)

 

[BLK18]

Thanks, that helps a lot. So for the engine build date mine says 17L30 which translates to December 30 2017, but that date was a Saturday. Is it normal for engines to be made on weekends?