More issues, this time broadband lines.
To summarise - a routine upgrade this morning resulted in a problem, but only when the last box was upgraded. We had upgraded routers during the week, as we don't upgrade everything all at once. However the nature of the problem was such that only when the last box was upgraded did problems happen.
The effect was a few seconds with no routing, and then a period where all worked. This repeated for around 6 minutes until fixes were applied.
We can see the cause, but this effect was not foreseen, so we are looking in to how we can avoid such issues in futre.
Sorry for any inconvenience.
Note: This would not have causes broadband lines to drop sync or lose connection at all - this was entirely a routing issue to the wider internet.
The issue is exactly the same as we had in Maidenhead so has been fixed quickly.
There have been reports that some parts of the internet damped flapping routes for some minutes after we applied a fix. These seem to be relatively few and far bewteen as overall traffic levels returned to normal levels immediately. Obviously there is not a lot we can do over such policies in individual ISPs.