On piebald horse, Diana to have recourse to .... (3,4)
I believe the answer is:
dip into
'have recourse to' is the definition.
The definition and answer can be both to do with social activities as well as being verbs in their base form.
Perhaps they are linked in a way I don't understand?
'on piebald horse diana' is the wordplay.
'on' means one lot of letters go next to another.
'piebald horse' becomes 'pinto' (I've seen this in another clue).
'diana' becomes 'Di' (Di is short for Diana).
'pinto' put after 'di' is 'DIP INTO'.
'to' is the link.
Can you help me to learn more?
(Other definitions for dip into that I've seen before include "Browse" , "Partake of, not finishing" , "Sample" , "tap" , "look at briefly" .)