Moving large workpieces around be a lot easier at .1G than at .5G.
The original question was about moving a Jumpship to a jump point under their own power. In this case, a tug is far more effective.
I suggested encrypting the destination's coordinates into the computer of the jumpship. Include the shipyard's movement algorithm in that encryption. So the jump ship knows that every third Saturday, with a date ending in a prime number, the Shipyard will be within a million miles of a point, 101 million miles, galactic South of the systems nadir point.
That is obtainable data which can be captured by either intelligence efforts or by the capture of such information before it gets purged.
Or the shipyard cuts thrust before the delivery is scheduled to arrive. Then when the jumpship arrives, they broadcast an authentication challenge. That challenge is picked up by a relay sat that links to the shipyard via tightbeam transmission. To prevent someone from guessing the shipyard's distance by doing some speed of light math, procedure is to delay all responses by some random time interval.
Broadcasts can be traced, and if you aren't careful, even a laser-link can be tapped if someone is on the right path. Again, the problem isn't the jumpship, but leading the dropships to the station.
Okay, lets get even more evil than that. The relay sat has a directionally1 blind receiver, and it has 6 separate transmitters, all firing in different directions. So if a bad guy grabs the relay sat, they know that the target is somewhere in one of six 1ox1o cone. If they had the proper challenge code, they could make some guesses at the range but again, we are going back to needle and haystack.
Transmission strength can narrow the distance down so long as you have a direction, if one has the proper equipment.
In the meantime, the shipyard can send a tight beam transmission to a jumpship sitting on standby, then go to silent running. That ship jumps out and comes back with the cavalry.
They would have to be under complete silent running before that, too, otherwise, they can be traced by their transmissions that were going on before. If your primary defense is to be a hole in space, then you need to be constantly practicing to be a hole in space. This situation is no different from ballistic submarines (though for obviously much different reasons). When they get in to a position to communicate, they are at their most vulnerable and trackable. They don't just practice silent running when they know someone bad is around, they practice it all the time.