Simply not the case.
I examined several BA etickets on the flight.
Not one mentioned the flight was being operated by IB and not one mentioned that catering to normal BA standards was not applicable.
Although I was aware of the no free food and drink, including water on IB (which is a disgrace and is against Spanish Law), I was using paper BA tickets, booked via BA's website. There was no notification of this being an IB flight to the normal unaware passenger, on any paper work or that food and drink was a chargeable item.
The fault here lies with BA and not with IB, apart from water being a chargeable item. Under Spanish law, you cannot deny a person access to a drink of water, without charge in any bar or catering establishment. IB's aircraft now fit that definition and IB need to reconsider their charge for water.