Sorry, but these forums are mainly for players to talk to other players. Occasionally a community rep replies, but this is very infrequent. This isn’t the place to go for official tech support.
This, exactly. I’m also in the UK and play on a (different) NA server and I’m not affected either. I have friends in the UK that do have issues from time to time though and they’re all with the same ISP so we know it’s a routing problem with some ISPs.
It means your route to the game servers (Canada) are going through some places that are losing or slowing down your packets and at a guess you’re going via Level 3 Communications which seems to be where most of these problems occur. From what I’ve read on the forums Comcast seem to (nearly?) always send their customers via L3 to get to Square Enix, but other ISPs will use them as well, just Comcast comes up a lot.
You would need to do a traceroute to check and even if it’s not L3 it’s worth doing when you are having problems as it will show you where the problems are actually happening (so you can know who to direct your annoyance at). You can then give this information to your ISP so they can route your around the bad places. They probably won’t, but they’re the only ones can directly change your route.
Most of the people in that thread you linked seem to suggest things were better with WTFast, further confirming it’s a network issue. WTFast (and other tunneling software) essentially work by trying to route your connection around bad networks that drop/slow your packets. This is something your ISP can (and should) do, although from what I understand getting an ISP to actually do that is unfortunately pretty hard and in some cases using another ISP might not be an option.
But just to clarify, Square Enix have no control over your Internet connection or how you connect to their servers. They can only control their servers and local network, they can’t influence or fix if you go through bad connections to get them to.
Your router is only responsible for your initial connection to your Internet provider (wherever they are based). So whenever you do something on the Internet your router sends the traffic to your Internet provider and they then point it on to the destination, but essentially your router is only responsible for that initial bit of your connection, it literally routed the traffic (to the ISP).
Your Internet connection is only as good as all the hops it has to pass through to get to the destination server. So even if you have a super fast connection that is stable/reliable most of the time, if to get to the destination server your traffic is trying to go through networks that lose/delay them then that in turn has a knock-on effect for you, either slowing it down, or making it unreliable or both.
If you’re going from Canada to Japan it might actually be sending you round the long way (via Europe!) although you’d hope not, it’s entirely possible that the connection going round that way is more reliable so the ISP routes you that way instead of the shorter direction (via Alaska and Russia?). You’d have to run a traceroute when you’re having problems to see which way for sure.