Is this a profit warning or not? Tesco says half-year profits were overstated by £250m and some of that relates to “timing issues”. It says it does not know what the impact on full-year figures will be.

Where does the buck stop? Despite still being on the payroll, outgoing finance director Laurie McIlwee did not prepare the figures behind the August profit warning with the now sacked chief executive, Phil Clarke, the last executive director standing at that time.

What extra scrutiny did Ken Hanna, chair of the audit committee, give the numbers?

Is this a one-off error or is there a culture of aggressive accounting practices at Tesco? At the moment the focus is on the six-month period but the scope of investigation could widen.

Who is running the finance department at Tesco? It’s not McIlwee, and M&S man Alan Stewart is not due to arrive until December.

Can chairman Sir Richard Broadbent survive? His reign is increasingly looking like a car crash and his claims to have acted decisively to right the listing Tesco ship sound increasingly hollow.