Changing uni course before I start

Has anyone ever transferred uni course at the same uni without having to withdraw their other 4 options before their course has even started! (Would be from Marketing to Accounting)

Yes I changed courses in April before starting university. All 4 unis were very accommodating and allowed me to change after I sent an email request. 3 processed the change straight away on UCAS and 1 required me to send in a new mini personal statement for the new course. UCAS also gave me a month's extension on the deadline for choosing my firm and insurance because of the change.

Yes its possible, depends on how the uni in question admin works, best to email them directly.

Most likely situation (providing you meet the grade requirements & the new course is not substantially more competitive), central uni admissions will email the admissions director for the new course your UCAS application, they will check it say yes and central admissions will amend your offer on UCAS.