Prifix lists only the 4c Écusson official with a double overprint (Prifix 98a). But here also is the 2c Écusson official with a double overprint!
I was pleasantly surprised to find this double overprint in a box of Luxembourg stamps on old printed album pages. I had cannibalized these album pages years ago, taking out the used stamps, especially those with interesting cancels, to be soaked and sorted. Now, years later, I've finally gotten around to removing the mint stamps. This unexpected discovery made my long delayed effort seem worthwhile!
Has anyone else found this stamp with a double overprint?