Not sure if this bug has been discussed in a previous thread–I noticed others mentioning Fog of War issues, but as far as saw, it didn’t specifically mention the speed control.
While the throttle is set at double speed, the Fog of War doesn’t always tend to dissipate. Returning to normal speed will remove it wherever the settlers’ point of view is (but not everywhere they were while in the Fog).
Again, apologies if this has already been mentioned!
EDIT: Sorry, @SteveAdamo. I did find the bug mentioned in a second check. Could you discontinue this thread for me?