Jayne - I expect it was me that was missing the obvious, and feel sure that the reason for my failure was due to me making assumptions, which lead me to the wrong series of nos. The story goes like this..............
Jobling's own catalogue No. 2626 is not shown in Baker and Crowe - but had it been there, would have occured (I assumed, rather hurriedly) somewhere within 1935/36. So I extracted from the Blue Book all the Jobling entries from volumes 204/5/6, scribbled down the relevant Registrations Nos. (all 8 series Nos.), that covered this period, and shot off to Kew, thinking it was a done job.
Had I been looking more carefully I'd have seen that Jobling catalogue nos. similar to 2626 etc. did in fact occur much earlier than the period I was looking at.
quote from part of Bernard's very informative contirbution (in my link)................"There are at least 66 pattern numbers in Jobling's Weardale range, and that doesn't include different sizes!
".................and I notice that none of the eleven hundred series Nos. mentioned by Bernard is shown in Baker and Crowe.
The only trinket set included in Baker and Crowe is the Jade set no.12500 - so it would seem that a lot of material and data is not included, maybe you should do a supplement Jayne
I know very little about trinket sets (compared to you), and it seems that it was Bernard who first came up with any mention of the 2626 set - at least in this current discussion - perhaps he can throw more light on the origin/date of it's Registration