This may have nothing to do with this ALSF 1 installation, however FAR 91.175 states in part: (3) Except for a Category II or Category III approach where any necessary visual reference requirements are specified by the Administrator, at least one of the following visual references for the intended runway is distinctly visible and identifiable to the pilot:
(i) The approach light system, except that the pilot may not descend below 100 feet above the touchdown zone elevation using the approach lights as a reference unless the red terminating bars or the red side row bars are also distinctly visible and identifiable.
This FAR lists the red side row bars, or the red terminating bars as a specific visual reference. My limited understanding is that there are US runways approved for 1800 RVR approaches under CAT 1, rather than the standard 2400RVR. This is the case if the runway has CATII lighting (ALSF II). That is the ALSFII with the long red sidebars and red terminating lights.
Could it be that the non-standard ALSF 1 shown with the notice is to ensure that lower minimums cannot be predicated on the limited Red terminating bars as this is a non-standard configuration? That's just my limited $.02