IP changes are not your concern. It is likely that your ISP blocks outgoing port 25, you can check with nc gmail-smtp-in.l.google.com 25 and if you don’t get any output its blocked. If you don’t have very many users on your Pterodactyl server, I would suggest just using a gmail account with SMTP in pterodactyl. If you have port 25 unblocked and want to selfhost email, mailcow is a great option and really easy to set up.
Not iTunes, but you can use libimobiledevice to backup an Apple device on Linux https://docs.mvt.re/en/latest/ios/backup/libimobiledevice/
I am currently working on this. I got a static IP and port 25 unblocked from my isp. I am trying to do opensmtpd and dovecot with dkim signing.
Ok so yesterday I had a static IP installed from ziply with business internet. I have not gotten a chance to test it yet (longer story below).
Ok so when they installed the static ip it went well until I had to setup the static ip on my eero router. I think I have been paying for 100/100 this whole time but it was not working because my house had a 15 year old fiber box. That was all replaced with a fiber running into the network room going to the ONT which has an ethernet that connects to the router. When I tried to set up the static ip it just bricked my eero and it would not connect to the internet. When I factory reset it it would not get past the setup screen even when I connected behind another router with a dhcp server. The internet technician tried for 3 hours to debug the eero and I tried for a few more hours. Today I just got a new Asus router system and it has been working well so far though I regret not documenting the port forwards required for each server and service better. I only have 2 routers now but I get full 300/300 speed inside the house and 100/100 outside on the edge of our property. I bought it with the best buy promotion where if you trade in your old broken router you get 15% off of a new one.
Alpine Linux edge