Strange HUD timing issue occurs when trying to spawn vehicles that have a long respawn time

On a map with the new deployment system, spawn a vehicle that has a long respawn time, get it killed then queue up to spawn another one.

The main HUD will correctly report the time to spawn, but the vehicle tab countdown will start to lag slightly behind as the timer counts down.

Not sure what could be causing this at all; perhaps some sort of cumulative floating-point error?