I rang FAO last week, as this was my first year to do any of this!
I am claiming last finacial years as a lump sum, they dont do any of it over the phone anymore, you need to go to the FAO website and register to use the online services, then make a claim online, so I had to do that for last years (and I wont see any of it till DP does his tax, wish he would hurry up!!) then do another claim for this years so I can get fortnightly payments.
HTH.