[julik]

This ELAC version is 100-something, and the A320 first flew around 1988. Why the updates - for example, there are updates to flight control law transitions, like after 1991 where the aircraft would limit flight control inputs during landing, thinking it would be preventing a stall - because it would not go into the flare law appropriately. See https://en.wikipedia.org/wiki/Iberia_Flight_1456

The cause could have also been an extra check introduced in one of the routines - which backfired in this particular failure scenario.