Blondie....are your plants on top of electronics??? I thnk they are by your . Supposedly, electronics are bad for plants if they are sittin on top of the electronics....You may want to try movin 'em around somewhere else....have they always been on the electronics? Do you have other 'chids on your electronics? I don't know, but that's my guess.
OK, I'll just jump in here and predict you are seeing the effects of the plant sheding the old leaves. Yes it does happen suddenly (like 2 days or so) and it's nothing to worry about. Your plant looks great to me!
Seriously?? OH PHEW!!!!! That thought didn't even cross my mind. When orchid leaves shed on these big ole plants, do they just fall off all on their own? As in I should not whack them off?
I've always wondered about that big, leafless bulb in the back. It's all starting to make sense now... (feels dumb)