NHS access while documents with Home Office

[Elizabella]

Does anyone have experience with accessing NHS while all your identification documents are with the Home Office? I've just got a somewhat scary letter saying that the front desk of the hospital could deny me treatment if I am not able to show my passport and visa.

Is proof of application enough? I am applying via the EEA(FM) route and have a COA. Not sure if this cuts it, though?

I also don't have my driver's license at the moment as I just passed the test yesterday to upgrade from automatic to manual. I have to wait at least a week for the new one to arrive, but have an NHS appointment at a new hospital Tuesday.