It happened to me a few times, but immediately logged in without delays. I think your issue depends your internet gets disconnected by your isp, as long as the ip address is changed.

I'd suggest the best course of action is trying to solve the stability of your connection with your isp, it is no likely a game will be changed to workaround an external problem. Check also the power, a loose power cable connector can turn off your modem and force a reset. Or any other hardware cause. ISP doesn't force DSL resync often and it is likely the cause is on your side. Check with their support staff too. It happened some ISP force connection drops to stop torrents and alike, and thinks xiv is a torrent, check it too with them.