I don't see a time set to the announcement, so keep your eyes and ears peeled in case they want to make this in time before the gilts market opens in around 2 hours' time. Expect more U-turns to the mini-budget announced by Kwarteng and Truss before as the government now tries to do damage control. From HM Treasury:

"The Chancellor will make a statement later today, bringing forward measures from the Medium-Term Fiscal Plan that will support fiscal sustainability.”