main Apple Mail app blocked on Eduroam in UK

I have an iPhone 13 mini - using automatic date and time and iOS 16.5. Everything is fine on 3/4/5g and on almost every wifi network except Eduroam. I have downloaded and onfigured the Eduroam app and can browse the internet just fine at university but I can't use Gmail via the Apple Mail app.

The network configuration of Eduroam at my 3 universities blocks certain risky network ports and as port 465 is now considered a non standard port it is blocked automatically on their Eduroam configurations. But the deprecated port 465 is hardcoded in to Gmail setup of the Mail app by Apple and it doesn't allow you to change it: the SMTP outgoing mail server/port details are automatically set by Apple.

Port 587 is not blocked by Eduroam providers. This is the port Apple use for their iCloud email in Mail. Gmail itself supports both port 465 for legacy clients and port 587. The Gmail app from the AppStore does not suffer from this issue so is likely using port 587 to avoid being blocked. So why is Apple Mail hardcoding port 465 still?

I have tried deleting and re-adding the Apple Mail Gmail account but no change.

Level 2 Apple support did not help and said I should go back to my university- but I have this issue with Eduroam at 3 institutions and university wifi at one so I think the problem is clearly Apple's odd use of the deprecated port 465 for the main iPhone mail app.

What can I do? I don't like the separate Gmail app although it works on my iPhone. It is a nuisance having to toggle wifi off and on to use Gmail via my Main Mail app while on university wifi.

Thanks