So, the Leopard 2A4 was manufactured with 2 different armour layouts – B-tech armour for batch 1-5 (2A0-2A4) and C-tech for batch 6 onwards.
It seems all (in German service) were upgraded to C-tech by 1992/3.
However, what armour do some early export 2A4s have? For example, the Swiss Panzer 87. The first were delivered in 1987, which was pretty much in the middle of the production cycle for the German 2A4 – at which point some still had B-tech, and some were beginning to receive C-tech (I believe).
Which ones did Switzerland have? If they produced all B-tech ones, did they eventually upgrade to C-tech like Germany did?