Hi there,
Contact the admissions officer, they’ll be able to tell you more about the process specific to your university.
I went through the same process last year, having received an offer for the masters in Feb, and I did not get confirmed by the university to have an NHS bursary.
Each university only gets so many bursaries allocated to it, so they will allocate them based on some form of decision the university makes.
You won’t actually get your bursary for a few weeks until you’ve enrolled and your attendance is confirmed, so if they’re asking for a prepayment of any fees, then you should check with the finance team what this looks like and if they are flexible to making any adjustments