Understandable as it's a lengthy, repetitive process. I think I've answered my own question, but does the lower RH window only have one set of stepped bricks because another part of the building abuts up to it?
I admire the accuracy of interlacing the bricks and stonework shown previously. I had a similar situation on a bridge portal (that was large stone blocks meeting rough coursed stone) and couldn't manage such a neat join line.
With reference to an earlier discussion, I seem to recall reading somewhere that, when laminating plastic sheet, there should be an odd number of layers, with alternate rolling directions (like plywood) to avoid warping. I suspect your heavy bracing is a more effective approach.
Lovely work, as always, by-the-way.
Dave.