It's always interesting to see who takes caretaker control when there's a sacking, I was under the impression that JED and kerslake came as a pair - they've worked together for several years and if one goes they both go.
Kerslake will be gone soon enough, club need someone to run things who isn't the manager. They'll still be paying Kerslake so might as well be him.
Pretty much standard practice for the assistant to step in. In fact I can't remember a time when we've sacked the manager and the assistant at the same time.