Rumors suggest the Royal Government doesn't have a need for their intelligence services in Sirius any longer. I mean, the Royals are in Sirius in 4.86. Shooting one house up and trading with another. One facet of the Gallic Junkers will be to continue providing intel on Sirius, but that will be to a far smaller degree as Gallia will have a presence in Sirius, unlike before.
Another facet is the ability to gather intel on the criminals. You won't be able to do that if you are at war with them. Not like you could if you played the middlemen like normal Junkers do.
The rumors enforce the role of a group that play both sides of the table, but are wise to ensure they can't be caught doing so.