In my line of work I look at contractors contracts for defence. If for example I see a manager working on contract A as a full time equivalent and then I see the same manager on contract B as a full time equivalent and both of those contracts overlap in a time period. This would be classed as double accounting and the funding for say contract B would not happen until contract A has finished. As I see as Mancini is, if both contracts are running side by side then city would have to prove that he conducted other work for the group other than managing city. If they could not prove that I can see why prem league would deem this as extra non declared payment. I'm sure
@Prestwich_Blue could go a bit deeper into it, I'm only on a certain pay grade and know my place!!