I think this is linked to a story in the Torygraph from a few weeks ago; it was covered in some depth over on t'Army means.
If it is the same story, then it refers to the members of the AFPS getting a commemorative badge; it may look like a medal by dint of having a ribbon.
It is not an OSM.
So if this petition is inspired by the Torygraph story, then it is based on a false premise and is utter horlicks.
It may be, though, that it is in part inspired by a chap who is leading the campaign for the award of a 'National Defence Medal' to those who have served but who were not in receipt of a GSM or similar because they did not go on operations. Remarkably, this effort towards the 'NDM' has succeeded in
annoying members of Arrse to the point where they sympathise with the MPs involved in AFPS - and getting members of Arrse to side with any MPs these days is one hell of an achievement!