Finish travel at the estimated time, when there's a dance (6)
I believe the answer is:
veleta
'a dance' is the definition.
(a dance to waltz music in triple time)
'finish travel at the estimated time' is the wordplay.
'finish' suggests halving the letters.
'at' says to put letters next to each other.
'the estimated time' becomes 'ETA' (short for Estimated Time of Arrival).
'travel' with half the letters taken is 'vel'.
'vel'+'eta'='VELETA'
'when there's' is the link.
(Other definitions for veleta that I've seen before include "A form of slow waltz" , "Fast dance in triple time" .)