Very soon (2,1,3)
(Other definitions for in a bit that I've seen before include "later" , "shortly" .)
(Other definitions for in a jiffy that I've seen before include "almost immediately" , "Before you can say Jack Robinson" , "Instantaneous" .)
'very soon' is the definition.
(I've seen this before)
This is the entire clue.
(Other definitions for any minute now that I've seen before include "Very shortly" , "Very soon (informal)" .)