Spell mistake in online passport application

Hello,
I am applying for first British passport after naturalisation.
During the application I have done a spelling mistake on my second given name which was noticed by my referee, confirming my identity. The application is already submitted and paid.
I contacted Passport office help line and they advised me to send hand written letter outlining the mistake to address which I will receive when my application is being processed.
I am a bit confused at the moment. Does my referee need to confirm my identity with the misspelled name and then my application will be processed and I will get a confirmation email with instructions where to send my documents and that explanation letter, or I have to wait Passport office to proceed my application( in my opinion would not start until referee confirm my ID) and and then receive that email with the instructions?
Any help would be appreciated
Thanks in advance

Not familiar with the scenario or what document they are sending you, though there are ongoing issues with certificate and foreign passport showing different names.
However, it shouldn't really be a problem as your certificate and foreign passport should show the correct spelling (presumably) so I'd expect it to be an admin exercise. Let us know what happens.

Quick update on my case:
I sent a hand written letter together with my documents explaining the mistake. Everything is sorted and the passport has a correct name on it.
Thanks

Thanks for the update - good to know it’s sorted.