Each shelf had 128 subscribers and on closer inspection of this picture you can see that there is a newer version of the ROF 131 875/42 LIB line card with the cable connected to the lower B*1F position. This card was manufactured in 1988.
This style of card was to be later seen on the BYB202 Line Switch Module (LSM) magazine with product code ROF 131 4441/2.
Each had 8 subscribers per card and are know as LIC8.
The other LIBs in this picture were manufactured in 1987. The oldest card in this subrack is from 1983. The build mechanics for this type of equipment are quite different from the later BYB202. In AXE102 the magazines are installed into a large frame which makes up the suite. In BYB202 build each of the magazines are mounted into racks.