Character movement speed not replicating

I’m trying to get network prediction working with movement, and I’m trying to implement a sprint ability. I store my bSprintPressed flag in GetCompressed flags and I set it in SetMoveFor also and then read it back in UpdateFromCompressedFlags. I’ve done pretty much everything from this example: http://error454.com/2015/03/20/ue4/movement/replication/

What’s weird though, is that it only works on the client. The server player’s movement speed doesn’t change at all when sprint is pressed. I thought it was just not getting the flag, but I added debug logging to see if the sprint press flag got set on the server, and it does. I simply implemented GetMaxSpeed based on the value of the bSprintPressed flag. What am I missing? I implemented GetMaxAcceleration too, but that didn’t help either.