Changing the IP address of your service is possible but only if there are some issues with that IP address. In any other cases it's not possible.
No, once a port has been allocated, it can no longer be changed over the entire active period of the service!
Only if the product will be updated to a package that includes dedicated port and the product doesn't have a dedicated port.
Dedicated servers have an activation period of 2-24 hours depending on region.