Hi Debbie
I would feel a little inclined to check into this change further.
Its quite feasible - although not common - that the iban number could have changed - but its really strange that they have changed your account number.
Any bank accoun in Spain is comprised of 20 digits -
the first 4 being the actual bank - Santander, Halifax etc.
the 2nd set of 4 numbers identify the branch office - Marbella / Fuengirola etc
the 3 set - whch are just 2 digits - identifies what type of account you hold
then finally -
the remaining 8 digits are your individual account number.
Have they changed the whole sequence of numbers?
Did they give an explanation as to why?.
I'm really surprised at all of this-- if they sent the letter by ordinary post - you may never have recived it & not have known and could have been directing people to pay into the wrong account..
Or did they send it registered?
Kind Regards
Jean