How would I put private resits on my UCAS application?

Hey guys if I choose to resit my GCSE maths and do a higher tier and successfully attain a good grade (at least a 6 so I can be considered in other unis). How would this work on my UCAS application, I intend on doing the resit in a private exams centre during year 13.

You can only put your achieved qualifications in your ‘Education section’
The only predicted grades on your UCAS application are your A Level ones

This is incorrect

You must list ALL completed and pending qualifications in your education section.