There's no small print with disclaimers, and there's no attachment or link in the offer letter or CAS referring to any other fees - the offer letter clearly states that
"This offer is based on a fee status of aaaaaa with a tuition fee of £yyyyy
Your fee status determines the level of tuition fees that you will be charged. It has been assessed using the information that you provided on the UCAS application. The University's fee status policy can be found on our website. If you believe that your fee status has been incorrectly assessed please contact us to request a Fee Status Enquiry Questionnaire. Please note we will only assess Fee Status queries made within 30 days of this offer notification."
There is a link to the university's website which includes a section on the fee status page stating that individual offer letters contain the amount that each student will be charged.
I would also emphasize that the offer letter provided a 30 day window for me to querie the the assessment amount. The University had 5 months prior to my acceptance to amend their offer.
The point is, not what the rates were or should have been, it is about the terms and conditions i was presented with when i accepted the offer and expectations set by the University. As i understand once an offer is accepted it it becomes a contract and would need to be amended by both parties. Or by some formal process in which an error was discovered and corrected within a reasonable period of time The question is does a university by some special virtue have the right to simply invoice a different amount than was presented in the offer letter and 5 months later in my CAS letter; And when i enquired about it, can they simply write it off as a computer glitch due to a dated price being sent in my offer letter?
To put this another way; Imagine i entered a contract for services for £x and after going through a lengthy decision process and a significant and costly preparation process to meet the terms and conditions of the contract, at the start of delivery i was presented with an invoice for 20% more than the contract price with no explanation. And when i went to pay the invoice and noticed the difference, I enquired and weeks later was eventually told, "Sorry, the price we negotiated and signed for was wrong, it should have been £y but there was a computer glitch which is why our bid had the old price of £x. Our prices went up and It seems that £y wasn't in the system at the time we initially prepared our bid".
That is exactly what has transpired here