Administered Pricing started in QLD on 12 June and extended to all mainland regions on the 13th.
AEMO directions and intervention pricing were introduced that same day and all market regions were eventually suspended from 14:00 15 June until 04:00 23 June.
The suspension, combined with intervention and administered pricing is a complex arrangement that was imposed in minutes. Amongst other things it caused large gaps between the values you should bid versus the values you get paid; automated bidding software cannot cope.
Asset owners who did not understand very quickly what had happened, and who had not actioned the correct response, risked losing significant sums of money.