Cattleytonia Spots, Old Leaf Yellowing, When to Repot

[Ginger9899]

Hello, I have a Cattleytonia Why Not hybrid and have been caring for it like a Cattleya because I could find no info on Cattleytonias specifically. I had it a year in September and it rewarded me with a gorgeous (if small) rebloom. It is in a bark mix on a West facing screened porch and gets blasted with several hours of direct sun each afternoon (this is the only place I have had it where the leaves were close to a healthy green). It has grown 4 new pseudobulbs since I've had it and lots of roots that all look healthy.

I wanted to check and see if it is probably normal for an old leaf on one of the original bulbs to yellow, and if I should remove it or let it do it's thing.

Also, all of the oldest growth has had these black spots on it since after I first got it and gave it more sun, I was told it was normal spots not something to fix by a friend so I haven't worried, now there is one on the oldest "new" pseudobulb, the one that flowered for me in September, does this look like something to worry about to any of you?

I also wonder if I should repot it and the best time, it had been in this pot and bark a year and a half now, and the bark still looks ok to me.

Thank you so much for your help, I want to post multiple pictures but can't for the life of me figure out how to get more than one attached :/

[Ginger9899]

I tried again, it still will only attach 1 image? Here is the yellow leaf anyway.

[james mickelso]

When cattleytonia pbulbs, like most catts, get old they shed leaves. Catts store nutrients in their pbulbs and when this storage function stops the leaf is no longer needed. So the plant casts the leaf off. The pbulb is now storage for the newer pbulbs. The leaf looks like it might have a bacterial infection like guignardia or polysticia. Check out staugorchidsociety.com

[Ginger9899]

Thanks James. I checked it out and think its possible. I went ahead and cut the spotty leaves off, save for the couple with only 1 spot. The new growth is of course clean and still there. I also sprayed it and soaked it in the only thing I had - Physan 20. I know that may not work for this but I didn't think it would hurt. I'll keep watch and see if more spots pop up in the future.