Assuming your E430 is like every other vehicle I have ever owned and/or checked oil on (which is a lot), the difference between the high and low marks is 1qt. I believe this is the case even on my 4.5 - which holds 8 quarts. If it's at the low mark and I add a full quart, it's sometimes slightly over the high mark.
Therefore, you've not even used 1 qt in the time between oil changes.

If your consumption of oil between changes is less than the difference between the high and low mark on the dipstick (not the bottom/end of it, just the low mark) then I wouldn't give it a second thought.

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Current:
2021 Charger Scat Pack Widebody "Sinabee"
2018 Durango R/T

Previous:
1972 280SE 4.5
2014 Jeep Grand Cherokee Limited "Hefe", 1992 Jeep Cherokee Laredo "Jeepy", 2006 Charger R/T "Hemi"
1999 Chrysler 300M - RIP @ 221k