I have 2 Schlumbergera truncata, this orange as well as a white one. It was in flower in December and it's in flower again: on Easter Sunday, though not near as floriferous as in December. Same with this S. birdgesii, but it's a much larger plant and must have easily couple of dozen buds and flowers. This particular plant is a family heirloom and we've had it for well over 40 years, it was a cutting from my wife's grandmother's plant... We took many cuttings from it when it finished flowering mid-January and many of those are in bud as well.
Schlumbergera bridgesii is a synonym of S. russelliana. Note also: "Schlumbergera russelliana is mainly grown in the form of its hybrids with other species of the genus, particularly the hybrid S. russelliana × S. truncata, which has been called S. × buckleyi (T.Moore) Tjaden or S. Buckleyi Group" Schlumbergera russelliana - Wikipedia
