The recent router upgrades have now seen some issues (last night). This means we expect to do more upgrades (or downgrades) over the next few days. We'll know more later today. If there are further issues this may end up being done during the day even, but this looks unlikely.
One of the routers showing problems (a.aimless) had a further issue today, and as part of the defensive design of our kit has automatically downgraded to the previous release. We are still investigating the cause of this issue.
We have a much better handle on the problem, and it looks related to "stuff" out on the internet having an unexpected knock-on effect on our routers. We have some plans for further changes that will address this.