It should update soon- mine only took about an hour after I changed my home address! You can assign seats for all the passengers on the booking, and at T-72, the bulkhead seats are often released so you can select these- a big perk of being Silver! Try and get seats 33ABC/HJK as these are very good seats in a smaller cabin of just 4 rows!

You can also take him into the LHR lounge which is a great airline lounge, they have a buffet food selection which is meant to be pretty nice! Flying in Y if you are Silver/Gold is not a bad experience- when can save you £1500 over CW I would just go for Y! Next year I may do a LHR-JFK-LHR in Y!

Have a great trip, and enjoy being Silver!