These are all in bloom today, so I decided to take a group portrait. Upper right is from Orchids Ltd.; lower right from Wübben Orchids; upper left is from Plested Orchids via Sue in Bristol; and the 2 pale ones on the left of middle are from Ecuagenera.
Its possible. Sue posted me her notes, she kept an index card about each orchid she bought, who from, when she repotted etc. Looking at the card it appears that she bought 3 seedlings fresh out of a flask that came from EYOF. I'll have to ask her. There is a note further down the card that mentions Plested Orchids, but on closer inspection that appears to be who she sold a bit of the plant to. She bought this in any case as a seedling ex-EYOF in May 1993. So could be a 4N. I'll have to take a closer look by daylight tomorrow.
My favourite of these is the plant I got from Orchids Ltd, made with a flavum besseae. I especially like the elegance of the shape. Took me a while to appreciate the colour, but it has grown on me over the past few years.