Moving on to Hereford, a drink to have first? (3,3,3,4)
I believe the answer is:
one for the road
'have first?' is the definition.
I don't know anything about this answer so I can't judge whether it can be defined by this definition.
'moving on to hereford a drink' is the wordplay.
'moving' indicates anagramming the letters (letters are moved around).
'drink' indicates putting letters inside.
'on'+'to'+'hereford'='ontohereford'
'ontohereford' with letters rearranged gives 'onefortherod'.
'onefortherod' placed around 'a' is 'ONE FOR THE ROAD'.
'to' acts as a link.
Can you help me to learn more?
(Other definitions for one for the road that I've seen before include "Individual presumably against railways" , "alcoholic drink" , "not for rail traveller?" , "Traveller's last drink" , "The ultimate drink" .)