Admin @ lemdit.com - Roam free!
Have you thought of self-hosting mailcow? https://github.com/mailcow/mailcow-dockerized
It’s very easy to set up and fairly straightforward to maintain, if you have a static IP and it’s not impossible to get a PTR record then I highly recommend it. Yes you’re self hosting your own mail server but mailcow vastly simplifies this.
Alternatively plonking it on the right VPS can also work.
In practice UPC will probably have some kind of fair use policy buried in its terms of service - your best bet is to go through those terms and see what you find. Fair use typically means they will start throttling you beyond a certain point. Most ISPs keep this reasonably vague (e.g. if your usage is in excess of what they deem to be reasonable, but no actual data amounts defined).
Not all ISPs have a fair use policy though, and typically you’re better off on large ISPs where your usage doesn’t really stand out that much.
It’s not a mass exodus. There was a sizeable influx of people from Reddit to Lemmy/kbin, sure, but that’s measured in the (low) hundreds of thousands. Reddit has hundreds of millions of active users.
The reality is it’s not even close to a mass exodus, not yet.
This is a Lemmy-ui bug, not related to CDN/cache.
I had submitted a bug report for it some time ago but it’s not that urgent in the great scheme of things so they didn’t get around to it yet: https://github.com/LemmyNet/lemmy-ui/issues/1865
(the report speaks about this happening after you log in, but it’s the same thing).