Makes changes to notices covering workers (6)
I believe the answer is:
amends
'makes changes to' is the definition.
(I've seen this before)
'notices covering workers' is the wordplay.
'notices' becomes 'ads' (I've seen this before).
'covering' is an insertion indicator.
'workers' becomes 'men' (man is a kind of worker).
'ads' going around 'men' is 'AMENDS'.
(Other definitions for amends that I've seen before include "Makes minor improvements" , "They're made to compensate" , "Make these to atone for wrong done" , "Alters and improves" , "Redress" .)