Hi, Alan,
Apologies, the guest was me on a work computer.
That's interesting. Yours is the only other Jeffries style duet converted anglo I've come across. I've had mine nearly 40 years and bought it from Crabbs'. It is a Wheatstone hexagonal ME/MB 62 button 4-row which was in CG concert when I bought it. I converted some of the surplus seemingly random accidentals into a full 2 octave low D and A.
Although it's a Wheatstone (28930) the general concensus among the sellers is that it is a jeffries duet conversion. I have another Jeffries duet by Wheatstone. I've often toyed with the idea of converting a Crane duet into anglo, or even, shudder, a McCann!