When you get pulled in by a wormhole you can limit the speed at which that happens to the server speed limit by pressing any movement key.
Also, when you deactivate overdrive while travelling at maximum overdrive speed you will slowly slow down, but if you press a movement key the ship will instantly travel at server speed limit.
Both seem to suffer from the same issue, any thrust input auto sets speed to max allowed server speed if you are above it.
How to reproduce:
# find a wormhole, get in a shipcore
# when you cross the max server speed, press any thrust key (W,S,D,A,...)