There is only one person who can in reality answer the question as to when Grayson should go and that's Simon Sadler..... with the support of his CEO and board.
SS knows what objectives were given to Grayson when he was appointed as manager, and how far adrift of those we are at any given point in time. Can SG continue to convince SS as to progress and prospects?
If Ben Mansford is doing his job properly (and I'm sure he is) he will be succession planning to achieve Sadler's longer term objectives on and off the pitch including the next team manager/coach. No manager comes with a guarantee of success.
A major factor in timing will be who can do a better job than the current manager, is he available and at the right price. Also SS needs to consider and build the football world's impressions of the new BFC : are we a knee jerk, short termist club who sack the manager at the first poor run, or does he want to be seen as a patient long-term planner towards the promised rosy future? Mansford is a football man who will be advising based on his wealth of inside knowledge.
We the fans have expectations, partly set by Sadler when he took over the club, of entertaining and ultimately successful football. Irrespective of manager we will, and should, keep reminding him of these but also need to trust him to make the right decisions as custodian on our behalf.
Grayson will go - that's football, that's life. When should he go? I don't know but I trust a man who will know when the time is right!
COYP