How serious is the problem of "stopping too far" next to the jet bridge? In the answer to the recent question &quot;How does an airliner adjust ...&quot;, there is the mentioning of the signal: &quot;STOP TOO FAR&quot;. But what to do if you see this?
In other words, if the airliner stops too far next to the jet bridge, how is this problem typically resolved? I was thinking about the possible approaches:

In my car, I would just drive backwards. But seems that the usage of the reverse thrust is somewhat frowned upon.
The aircraft will be serviced without the jet bridge (movable stairs, etc).
The aircraft will be towed backwards where it should be.
The jet way most often can be adjusted to compensate the unexpected location, the sign is just the warning.
No ATPL holder would ever make a mistake of this kind anyway.

Also, how often does this happen? Is this a very rare problem or something more common?
I can't tell you how often it happens, but the procedure is quite simple: stop the aircraft immediately, and alert the ground crew. It is then up to the ground crew to decide what, if anything, needs to happen. If the aircraft has just slightly passed the intended stop position, maybe it can just stay where it is. If it has overshot significantly, it may be required to push the aircraft back to the correct position with a tug. Worst case, the aircraft might have actually hit some obstacle (building, vehicle, jet bridge) in which case the aircraft or surrounding equipment might have been damaged.