I think you can call and *schedule* it if you have your case number. But, if I recall correctly from other threads, you'll need some forms that are IN the packet and you don't want them mailing the medical back to the Embassy before the Embassy has your information in the computer. So if you have your LND number and you have to book the train ticket within a certain time to keep the price, you can always try it and just cancel the appointment time if it doesn't work out.
p.s. have you called the State Dept to check on the progress yet? I called yesterday and they told me that they had mailed P3 on 5/20. He hasn't received it yet, but we're hoping it gets to him tomorrow or the next day. It should, based on others' reported data.
instructions for calling, lifted from some other post somewhere that i've saved on my desktop:
QUOTE
London Embassy:
The State Department is on 001 202 663 1225 then press 1,0,0 to talk to someone
They can tell you whether the Embassy has put the file on the system, saves you calling the premium rate line in London to ask!!
My fiance tried the UK number - to that Scotland call center or whatever - and they knew nothing. When I called the State Dept, US-side, about an hour later, they had it in the system and said p3 had shipped out already.