This is a very ambiguous sentence in English. It can mean.
Bruno and Anne only left the next day. (So after their trip to Versailles, they only had one day left. I can't believe that they only left (allocated) the last day for Euro Disney. )
(I was looking for Bruno and Anne last Monday. ) Well they only left the following day. You must have missed them - ils ont venu de partir / repartir ?
Did Bruno and Anne do anything other than leave the next day?
- No. That's all they did. They only left the next day
I'm trying to get the meaning/sense of the French sentence but the English is confusing.
Sometimes we say "they only left" meaning that "they (had) only just left."
The translation given in French is:
Bruno et Anne sont seulement partis le lendemain.