School going rapidly downhill - what if anything can parents do?!

[DitzyPrints]

Dd primary school has been outstanding for last 15 years (hasn’t been checked in 7 years or so).
Last couple years results have dipped, this year they have plummeted dramatically.
The head left nearly a year ago and the assistant head has been acting up but quite vocally isn’t happy about it.
Are the parents able to challenge the governors at this point?
Any advice very welcome thanks

You do realise there aren't many heads around now - hardly anyone wants the job! Wouldn't go back to that for £million!

And Joboy Headmaster - surely you mean headteacher?

Could there be a strategic plan to make bigger change.

Is the school likely to federate with another and share a HT?; is it likely to be waiting to become an academy?; is it likely to be closed?; does it have a budget deficit and a cheaper acting HT will be a saving?

All could be reasons for delaying an appointment.