Accessibility (broken foot)

Hi everyone — I have two Gold tickets, but it looks like my foot won’t heal in time for me to walk between stages.
I’ve heard Platinum includes shuttles. Has anyone attended this festival with accessibility needs before?
Tickets aren’t refundable, so I’m wondering:

· Can we upgrade from Gold to Platinum, or
· Do I need to sell my Gold tickets and buy Platinum separately?

Any thoughts or advice would be greatly appreciated. Thanks!