NOTE : Above information pertains ONLY to TAs in Asia/Pacific region. It does NOT APPLY to North American (ie Canada, US) or EUROPEAN agencies who have their own protocol to follow.
Currently Asia/Pacific TAs use all formats to try and get waitlists cleared - namely phone, fax, email, bribes even... and CX is trying to curtail all that in favour of doing everything on CRS. Though of course, the ones who do know where to get 'special' favours, would not need to follow protocol.
Having Oneworld elite status on your booking increases your waitlist chances. Though sometimes we still do need the extra help a TA can do.
Above does not pertain to award bookings!