I have changed the oil a couple of days ago, and I've noticed that the low oil pressure light stays on longer than normal. Normally, it goes out almost immediately (<1s) after starting the engine, while it sometimes takes up to 4 seconds now after the oil change. This only happens during a 'cold start', not when the oil is already warmed up (then it goes out immediately).
The oil level is fine and stable, there are no leaks, and the oil is a high quality 5w30 oil that is specifically recommended for the car; the oil viscosity is identical or nearly identical, I believe, to the previous oil (it was either 5w30 or 5w40). The oil filter I used was a high quality Bosch filter. The car works perfectly. Again; this only happens during a cold start; never during a 'warm start' when the engine oil is already warmed up, nor during driving.
I don't think it's a big deal, but I would like to understand why this is happening. I pretty much rule out a malfunctioning oil pressure sensor, since it only started happening after the oil change. Oil viscosity also seems to be okay, oil levels are fine, the oil and filter quality are both okay,...
I've thought about the clean oil being thinner than the dirty oil causing this rather subtle issue, but I have no idea whether this is true, let alone whether this can cause such a warning.