Spongebob

It’s related to the smoothing mechanism allowed under IFRS (GAAP does not adjusted the over/underfunded amount for unrecognized actuarial G/L). The unrecognized G/L sits in OCI until recognized.
I’m not sure if that helps much as far as the logic goes, but it seems like this topic is one of those things that it is important to know where IFRS is different from GAAP and the adjustment that needs to be made.