4 years Platinum charge, annual fee posted, called around 11am AWST, transferred to (I believe) Australian call centre. Asked to cancel, cited SQ deval and concierge app. Didn't go through the actual cancellation process as offered 200k MR points quite quickly to stay. Accepted, whole convo took about 3 minutes.
Did this last year too (think I only got 100k MR points though).