With the increasing amount of bumpf that is being jammed in to the FMC they were becoming clogged up with errant data. It was becoming an engineering function to pull the CB's of the FMC's every turn around. That would clear all of the latent data. Crews then started doing it if they saw it hadn't been done (it's easy to tell on a Boeing). However that totally isn't sop, hasn't been published anywhere and engineering probably don't know it's happening.
I wonder if it will have unintended consequences.