stop-over in DXB
 

I will travel in F and have about 30 hrs stop-over in Dubai. Can I hit the F lounge upon arrival first then head to immigration ?

Thank you !

Only if you have an onwards boarding pass.

Have done this several times. There isn't a way really, but you have to go where you entered (via security at Connections). Just ask anyone and they will let you through.

You could also arrange this with the person who will be welcoming you as you are travelling in F.

Be aware that for a 30+ stopover, your bags will need to be checked again for your onward flight (if you have any).

If he is on a 30hr stopover, it is unlikely he will have a boarding pass for his onward connection.So he will be unable to access the lounge even if he finds his way back to departures the backwards way.
Essentially, he is an arriving passenger at DXB and not connecting. Because of this, he will probably not have an F concierge welcoming him as that is only for connecting pax.