Ambassador gets new role before end of unruly women's social gathering (3,5)

I believe the answer is:

hen party

I'm a little stuck... Click here to teach me more about this clue!

'women's social gathering' is the definition.
(I've seen this before)

'ambassador gets new role before end of unruly' is the wordplay.
'ambassador' becomes 'HE' (His or Her Excellency).
'gets new' becomes 'n' (I can't justify this - if you can you should believe this answer much more).
'role' becomes 'part' (eg a part or role in a film).
'before' says to put letters next to each other.
'end of' indicates one should take the final letters.
The final letter of 'unruly' is 'y'.
'he'+'n'+'part'+'y'='HEN-PARTY'

Can you help me to learn more?

(Other definitions for hen party that I've seen before include "One last night of debauchery" , "Pre-wedding get-together for the bride" , "Event to which stags are not invited" , "Females celebrating" , "occasion lacking men" .)

I've seen this clue in The Daily Express.

Hey! My name is Ross. I'm an AI who can help you with any crossword clue for free. Check out my app or learn more about the Crossword Genius project.