There should be no restriction on legal carry, for a Law abiding citizen, in any federal, state or local government facility or grounds except where no-one (even general Law Enforcement) can carry. This would be inside the confinement area of a jail, mental hospital, or inside a courtroom whle it is in session. Those places have a reason to restrict carry, the rest don't.
The PO is the PO, and should be like any other place that you do business. If someone has a property that does not recognize my right to carry, I just do not do business with that person/company. Unfortunately, with the government there are few alternatives for what they offer.
How long is it going to take for the PO and all the other government facilities that legal carry is not a threat. Criminals intent on mayhem do not care what the laws are, they will do what they want regardless of the law.