Miltoniopsis and Brassia hybrid problem bloomers

[Kaykay]

Sorry it's been a while! I hope you're all well!
I've been thinking long and hard recently about what to do with 2 'problem plants' of mine. A Brassia Chieftain (longissima x verruccosa) and a Miltoniopsis Anneville. The Brassia, in particular, grows like a weed. In fact, it might be a candidate for the amazing blob-tripling in size in a year. Mltps also growing well. But, you've guessed it, not a sign of a spike from either of them. I've used the same fertilizing and light regime with them as I have my Oncidiums (Sweet Sugar and ornithorhynchum-both blooming like crazy) I've tried a rest period for the Brassia, diurnal difference is good for both. But zilch. Nada. Not a whisper.
Any ideas?
Thanks!
Kay
x

PS Sorry, realised I left out this crucial info. Mltps has bloomed in past (but not for me). Brassia I've raised from seedling, yet to bloom but now so huge it's bursting out of edge of 6" pot. 6 leads and counting...