Over many seasons of neglect of colt players, it is possible to be sacked, regardless of your performance. So be sure to offer deals to your colt players and promote them. In the case for this fix, the expectation was 6 promotions, but only 2 were made. This led to a penalty score from the chairman that brought down the average too far, and lead to the sacking even though the club was top of the league. This penalty has now been made proportional to the difference between the number of promotions and the number of expected promotions. This results in the sacking only occurring if the difference is very high. So promote your colt players, offer them deals. Many thanks to Luke for sending us his auto save and save game to highlight the issue.