Originally Posted by craigthemif

To go to T4S (the non-Schengen part) and back, you would need to go through passport control twice. Unless you are an EU citizen, that isn't recommended. Plus the passport control agent might ask to see your BP for T4S, in which case you couldn't go through anyhow. And it's not straightforward to get from T4S departures up to arrivals...

I recommend you just go to Dali together (T4 lounge), and then your partner can leave earlier than usual for the train to T4S.