ILR Premium Service - appointment booking system

[ssen]

Hi all,
I am a Tier-1 General and applying for ILR under SET(O); appalled to see the options for applying:

1. The postal service has an ‘average’ turn-around time of 6 months (could be much longer); not an option for me as I need to undertake regular work-related travel as a part of my job

2. The premium service comes with a hefty price tag. But getting an appointment is like hitting a jackpot because the online appointments are all always fully booked and there is no other way to get an appointment (they've stopped phone booking)

Has anyone found a reliable way to get an appointment?
I am willing to travel to any PEO in the UK.

Many thanks for your help.