Gurkha shoulder title - ?

[gurkharifles]

I recently acquired this pair of GR shoulder titles from an ebay seller. He was selling a few genuine buttons/titles of 3GR - from around the 1920's and this pair came with them.
The 3GR title is from my own collection but interestingly there was a pair of these being offered by the same seller from the same source. They had the makers name J H Johnson & Co. Aligarh UP stamped on the reverse ( the same as my example ) - I've photographed the 3GR example as the font matches the GR ( albeit the GR is larger - 17mm in height ).
I think if the GR titles had been offered on their own I might have passed - but given some "provenance" to the 3GR and the similarity of font to that used by Johnson - I thought I'd take a "risk". I'm aware that there's no examples recorded of a shoulder title with just GR and no number preceding it - but was curious enough to buy them.
Having shown them to Ashok he speculated that they might be a reserve Btn - before they were allocated a number ( but it was only a "guess" ) - it also occurred to me that during 1916 there was 3rd Btn raised for the 4GR bt due to a clerical error it was posted as the 4/3rd GR - I wonder if the titles could have been related to this confusion ? Will probably never know for sure .