Today we have updated the networking model that GTDNext uses to make it more stable and reliable.
While we haven't had any large downtime in the recent past, we do have to do much more maintenance on the system that we would prefer to prevent issues. This update changes how we do networking to prevent those issues.
important If you notice any strange behavior or have trouble accessing GTDNext directly after we make this change it is likely your browser is caching code and data. The best thing to do is refresh your browser several time via CTRL+F5
Let us know via support if that doesn't resolve the issue. (https://gtdnext.uservoice.com/)
James and Sergio