Originally Posted by jf841
There is a transit desk where they can check in if necessary, but Delta should issues boarding passes for the MXPPMO leg as well.
If they are flying Delta BizE they should have access to an arrival lounge to hang in for the 4 hours. Also, if the entire ticket is a business class ticket (this is possible even though the Alitalia flight is all Y), then Alitalia will probably grant lounge access.
Except that the tickets are on separate PNRs - Delta will only be able to check them in as far as MXP from JFK.
If there's an arrivals lounge, they'll have access but as it's on separate tickets, I doubt Alitalia would grant access to its departure lounge.
Welcome to FT,
jf841!