According to Dr. Christenson description, I think, the specimen from Philippines has yellow orange flowers unlike its counterpart which is dark orange and thats what they identify this as subspecies.

Here in Mindanao, I found Ascocentrum aurantiacum subsp. philippinense in Bukidnon but I didn't bother to gather it because I have 15 specimens in my garden which is enough as for my botanical specimen.

Jim Cootes will provide the brief details about this species if he does.

With regards to Dendrobium armeniaca, Coelandria armeniaca is validly published name. But as for my own interests and other collector's interests, we consider them as Dendrobium in different subgenus or section. Taxonomy is one of the most complex to study. That's why until this time, there is ongoing species reclassification.