I've badgered/reported to Garmin and Navteq (their mapping supplier) but around half the indicated speed limits shown on my Garmin are incorrect. Many limits in Derbyshire have been permanently reduced by 10mph.

Anyone have a definitive answer as to when/how often these data get amended?

I do update my satnav regularly from the interweb thingy.

When going through a random 30-40-50 mph cycle on the A6 it would be nice to have a clear back up as to the current limits. Noted several signs either missing or hidden recently- a good reason to have a back up- especially when it is illegal to have 30mph limit repeaters.

Edited 19 January, 201214 yr by gregoir

I've badgered/reported to Garmin and Navteq (their mapping supplier) but around half the indicated speed limits shown on my Garmin are incorrect. Many limits in Derbyshire have been permanently reduced by 10mph.

Anyone have a definitive answer as to when/how often these data get amended?

I do update my satnav regularly from the interweb thingy.

When going through a random 30-40-50 mph cycle on the A6 it would be nice to have a clear back up as to the current limits. Noted several signs either missing or hidden recently- a good reason to have a back up- especially when it is illegal to have 30mph limit repeaters.

Generally there are lots of repeaters for a 30mph limit, they are called street lights (or carriageway lights if you are Scottish). It's the other limits where you need repeater signs.