I've noticed, on several occasions, mainly on motorways, that my 2025 Superb L & K hybrid detects a lower speed limit and will continue for miles showing a lower speed than necessary. Where is the Superb getting its speed limit information fromm

I presumed it was getting it from GPS data like Waze does however on the A75, there are outdated 40mph signs for lorries see image and the car changed its limit to 40mph which is obviously incorrect. Therefore I'm thinking there is a front facing camera which reads the speed limit signs similar to it reading other signs which then flag up on the dash, ie narrow road, roundabout, wild animals.

As far as I can tell, it's a combination of sign recognition via the front-facing camera, and map data. The sign recognition seems pretty reliable. The map data, though, is of wildly variable quality - in some areas near me (northeast Wales), the data is wrong more than it's right. And unfortunately, when there's a discrepancy between what the car 'sees' and the data it's pulling from the onboard maps, it seems to give preference to the map data a lot of the time, so the correctly-detected limits from roadside signage are overridden by the incorrect speed limit data from the map.

There are a number of threads where people are complaining that it picks up long removed temporary speed limits. There are no signs at all to see now, but on the M1 and M4 it comes up with 50 mph at places where there were roadworks many moons ago.