Dendrobium bracteosum questions

[Calbears]

I bought this den bracteosum at the beginning of June. About 75% of the flowers were opened then and they've now fully opened. I'm really happy with this plant but am a novice orchid grower and don't want to kill it. There's one leaf that has turned yellow recently and am wondering if that's to be expected. Is this a deciduous den or not? I've read conflicting things. As you can see there's a new cane growing and I'm wondering what my watering/feeding schedule should look like through the fall and winter.

[plumania]

I was just reading in my recently bought book (Dendrobium and it's relaives)on Dendros that leaves on this one are deciduous after 2 years .

[WhiteRabbit]

beautiful!

[Calbears]

I just noticed, and you can kind of see it in picture 3, that there's a darkish area on the cane under the yellow leaf. It's a little soft. Is this cause for concern? Bacterial infection? I'll post a better pic this evening.