Was this a stupid move or am i paranoid

bvl

You are being paranoid. The car is fine, especially sticking with the conservative OCI under warranty. It was a bit silly to expect synthetic oil changes with the comps unless its expressly noted.

Nothing wrong with going back and forth between oils. Nothing. Car will run fine, no damage is done, especially using a 3K mile OCI.

The only thing I would be a bit miffed on is the use of 5/20 vs 5/30.

5/20 is common in the US to squeeze out a tad more MPG, but also a bit on the thin side. For a car that runs a bit warm, I prefer 5/30 or 5/40 if you are in the correct temperature range. Would not surprise me to hear you are consuming more 5/20 then 5/30 either. Not uncommon.

I personally bring my own Pennzoil Ultra to the dealer for my oil changes. Less expensive then the Ester and runs smooth for me. You do the same and the labor and filter should be free as part of your package.

- b