G1 Prowl variant?

I was looking over some of my stuff last week and noticed my old G1 Prowl has 'DIACLONE' written in his blue badge on his bonnet. At first I thought it's probably just the Diaclone version but it also has a rubsign which dates it a '85 onwards.
I've looked through hardcopy and internet guides and can't seem to find mention of this variation. Anyone else have this variant?
