I haven't seen any photos or documents that mention/show a 1915 issue of the original 1914 OWS badge.
Tom Tulloch-Marshall's article mentions that the oval 1915 OWS badge was introduced in "early 1915" and that a memo was issued on 27th March 1915 ,with illustrations of both the 1914 and 1915 badges , stating that "these are the only recognised Official Badges".
So it is possible that a 'short run' of the round badges were produced in early (Jan/Feb) 1915 with that date on them before the official 1915 badge was issued.
Unfortunately I can't make out the details/makers mark on the rear of the badge which may give a bit more information.
When the "unofficial" badges were banned and some workers (due to conscription etc) had their official badges/status removed Fred Spurgin produced a postcard showing a '1916' badge but I think this was simply to illustrate when the new policy was introduced.
I'll have to keep my eye out (and double check listings) to see if another badge appears !
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