Until I study the flow diagram I won't be able to answer completely.
Bet somebody here knows the answer already.

But... It it were picked up after, you might think that filter quality would effect oil pressure.
Unless a filter bypass exists and then you would not see any change.

Using the in dash mercedes gauge I never have anything other than the full 3 bar at all times while driving.

Which my friends and I sort of chuckle at.

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80 300D 340K Owned 30 yrs
83 300SD 440K Owned 9 yrs - Daily Driver 150mi/day
02 Z71 Suburban 117,000
15 Toyota Prius 2600 miles
00 Harley Sportster 24k
09 Yamaha R6
03 Ninja 250