Royal Mail Unadopted Christmas Stamp found used

Every week we get questions asking about details of stamps or for assistance in identifying stamps which may or may not be real stamps.  Long-term readers will recall the postal use of Olympic Gold Medal trial printings, and the parrots back in 2012/13.

Once upon a time I could remember the date of issue of most GB special stamps - at least up to the 1980s.  Nowadays I'm lucky if I can remember which year some issues were, let alone what time of the year, but I recognise most of them as being genuine - after all, I have written about them here and on the website, and stocked most of them.

Today I was sent a real stumper.  Obviously a Christmas 2nd class stamp, and obviously postally used, this one didn't ring any bells, and the writer hadn't been able to find it by searching the description on Google.

 

But Google also has a 'reverse image search'.  Most web browsers now allow you to type your search terms in the 'web address bar' at the top, rather than going to your favourite search engine, but if you go to https://images.google.com/ you get this search box:

and if you click on the black camera icon you can either enter the URL of an image, or upload one from your computer.  Doing this I found the website of the designer, Gaia Bordicchia.  They were produced for the 2014 issue but not used.   

I don't yet have permission to show all four designs, but you can see them here.  This is the Christmas pudding one shown as on the website:

So the question is, who produced the stamp?  My deduction is that it is certainly not a print from the website, because the perforations on the used one are torn, not die-cut, and if you were cutting out a picture printed from the web, it would be straight-edged either including or excluding the printed perforations.  So it must have been taken from a perforated sheet (or miniature sheet?).  Did Royal Mail produce some as trials - gummed trials are cheaper than self-adhesive?  How many of the four were printed, how many different designs, and how many were used? 

If anybody else has seen these, I would be interested to hear about them.  Meanwhile the investigation continues!

UDPATE
The comments below refer to Philatelic Bulletin giveaways, but these were not commissioned for potential use as actual stamps.

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