But 30mph is too fast to move past a stationary queue of traffic.
The usual recommendation for lane-splitting/filtering on a motorcycle is to go no faster than 15mph more than the traffic flow- this allows enough time to react to any unusual movement by the car in front of the one you’re overtaking.
The same applies here- any more than 15mph past a stationary queue of traffic is too fast to be able to stop if the next-but-one car pulls out.
