It's more a case of GRN taking control of the area (somewhat), rather than particularly caring for the Guild's safety. A few too many friends that are enemies of Gallia, and a game mechanic way of showing their presence in the Taus (since logging ships and RPing there might be too hard).
I'm not really a fan given it'll be shooting CR people, but that is effectively the intention so not a real complaint.
EDIT: As for the RP announcement, the GRN have been in the system for a hell of a lot more than four months. Add at least another year to that, going by the date that the neutrality agreement with the IMG were made (middle of 818 according to here) and 4.87 takes place in 820.
