Would this referee be as valued as...?

I'm studying through distance learning and kind of doing qualifications the other way around from the way there are usually done; foundation diploma in art and design first and then iGCSES or A Levels. For a BA Fine Art degree course at university, would a UCAS reference from an A Level or IGCSE tutor from a non-art related subject that I would have studied, be as valued, so to speak, as a reference from a Foundation Diploma in Art and Design tutor?

If you want to go on to do fine art, would you need A-levels as well? For most courses in Fine Art, admissions tutors are mainly interested in your portfolio, and you don't necessarily need all the traditional qualifications (although you will probably need at least GCSE English).

The best thing to do would be to contact universities you might be interested in attending and seeing which referee they would prefer. You could also check with them if you would need A-levels or if you current qualification would be enough.

The head of admissions at the university of Chichester says regarding the reference...."with a particular focus on the one that's going to be taken to undergraduate level."

https://www.ucas.com/advisers/references

That sounds then like a reference from a foundation art and design tutor would be favoured over a reference from a tutor whose subject I take wouldn't be furthered at university

Yes, it would. The university would be wanting to know what you were apparently trying to hide by not using the relevant tutor.

Wouldn't a university want the a reference from the most recent qualification done, regardless of subject? The foundation diploma will have been completed before other academic qualifications.

Well, it's usually the same person, but you yourself have quoted the relevant part where it says they want it from someone who can comment on your suitability for the course. It would look odd to have a reference commenting on your academic ability in subjects which you are not going to continue with when you have completed the course which is tailor made to lead directly into the degree you have applied for. It immediately looks as if you are hiding something.

The man I quoted is one admissions tutor at one University. I'm not intending to apply to that University. I don't think admissions are necessarily the same on this.

Then why are employers allowed to provide UCAS references and presumably many of the people who have employer references, what they did as a job may have no direct relevance to the course they want to study at university?

People get references from their employer because (usually) they have been out of education for too long for any academic reference to be still valid or available. Universities will always want an academic reference rather than a work one, but some people have no option and an employer's reference is the best they can do.

You've clearly decided what you want to do, so there isn't much point in my pursuing this conversation. I hope it works out for you.