There is no formal contract between the beeb and the public, only a moral one, and they seem to have delivered that which is the majority of voters choice would star as Nancy. Only that the voters decided who should be Nancy. The beeb and Cm will have a contract and there is probably a clause in there that states that the producer reserves the right to limit the winning Nancy's performances to a minimum of 4, max of 8.
The BBC should probably have made that clear, but the public who voted for the winning Nancy have essentially got what they wanted which was that that girl would play Nancy for the majority of performances.
You can complain to the BBC about their lack of clarity about small clauses in contracts between them and producers, but surely everyone must have been aware this could be so after Connie was originally cast to do 6, whether it then changed or not, a precedent had been set, so it can't be a huge surprise. But small clauses in everything are a complete nightmare and rarely divulged by a 'seller'.
CM and ALW came down heavily on Jessie's side, it is true. I think ALW is beyond reproach because he really praised both girls, and gave a caution to both girls. It is true he did, when asked, plump for Jessie, but this was surely offset by DVO and JB coming down heavily on Jodie's side. In fact, I think JB was so negative, that it became unpleasant to watch, and I don't think anyone else behaved quite so negatively on the show. It is unfortunate for Jodie that the producer didn't favour her, but I think it probably helped her pick up a few sympathy votes, without which the result may have been closer - who knows?
Write to the BBC and complain that they should have made clear that it might be 6 performances or 8.
Do you really think, though, that that would have prevented Jodie's fans from voting to give her a once in a lifetime chance in the West End?