Hi Den,
One of my colleague from Revi magazine wrote an article about 7th Staffel over Malta. See
http://www.revi.cz/en/revi/53_en.html and
http://www.revi.cz/en/revi/54_en.html . If I remember right (I am out of my home and the printed versions) there was mentioned there it was a longtime mistake when the hearts were interpreted as red instead of black. A colour photograph confirmed this (?).
Regards,
Michal