A "Q" on this facility....you have a warp point from system A to system B....System A has a SGSF....system B does not...can you close the warp point from A to B if your closer is in system B?....or because you have a facility in one of those 2 systems that warp point will always be uncloseable?
No, you can not close the WP. The System Gravitationl Shield protects all WPs that exist in that system, regardless of where the WP closing ship is located.