Charter aircraft are not specified by S/N and Rego on an AOC, although RPT are.
Yes, quite aware of that.
Who is the operator of the aircraft is the question, in my link above, neither BA or CA is listed as the aircrafts operator, so:
* Who has a written contract with the owner of the aircraft ( and pays the owner money every month ? ) ?, and,
* Who is invoicing the football club, or whoever is paying for the Charter ?.