Sorry PSQ my old mucker, but on this very rare, isolated occasion you're very wrong.
EGNOS is most certainly not a proper "constellation" - in the sense of an orbiting group of non-geostationary Global Navigation Satellite System (GNSS) birds. In the way that GPS, GLONASS, Galileo, Bei Dou and QZSS actually are proper GNSS constellations!
'Humble pie' time:
My mistake, Rangepoint is the US and GLONASS constellations (etc) plus Trimbles own 'RTX branded' correction signal, and doesn't involve EGNOS.
Apologies to @Tractor Boy
(But you were still wrong about the GLONASS not being a part of RTX )