At last I tackled my threaded in Birka project again and this time I got it back on track. Once I backtracked enough to know where I'd gone wrong and why, and to establish where in the pattern I was, I marked my place, then hastily returned to the computer and made a turning chart specifically for the "reversed" turning pattern.
It was on coincidence that I'd been derailed about an inch after I'd changed directions. The first time through the reversed sequence I was excruciatingly careful to turn everything the right way, but on the second time through I began to relax and weave "normally" again, convinced I'd gotten the direction change to work. Unfortunately I was simply using my original turning cheat sheet turned upside down as my reminder. Well, clearly I was a bit inconsistant in remembering to reverse everything I came to. Some things were reversed, and other things I'd done just as they read on the page. Disaster!
I've woven up another couple inches with my new "reversed" turning chart. I did it in different colors even so I wouldn't mix them up. It seems to be working. No doubt I'll find my rhythm with this one just as I did with the Rams Horn and variants and the Anglo-Saxon diamonds before it. Till then, I'm sticking to my turning chart like felted wool.