APP, I'd never seen or heard the word at 9 A! It's definitely an odd one, but the clue does lead to it..
A four letter word for 'Walk', take steps etc, with the usual 'that is' and the common 'certainly' (yes, agreed etc) inside.
App, thanks - and glad I could help. Yes, it could be a bit of a challenge having a new setter to get used to - it'll make us work a little harder, I expect!
I found the two four letter down solutions which were fully checked unusual, though I’ve not been doing Azed long enough to know if he might have done this in the past.