M&P Shield sear

So just for fun and to try and figure out why my shield has a very heavy trigger, I took the front and rear block out. It has a heavier trigger spring than my full size. It also has what looks to me like the old style sear, the oval type trigger bar nub. I bought this shield a full year after I bought me full size, which has the newer tear drop trigger bar nub. Any one else notice this on your shield?

My shield is not the earliest model and right now I don’t remember it’s shot date. Trigger was heavy 6.5+lb and had the striker block spoing.
I added an APEX Shield Duty Carry Kit, trigger pull is 4lb 9oz average. Factory trigger, longer pull and short reset. clean break.

I noticed it for the first 200rds. I can’t really anymore, or have gotten used to it.

My pull on my shield was over 7 but used a apex sear and dropped it to 5#.