BT have a series of planned work that involves them replacing cable bundles that include our hostlinks - our interconnects into BT's network. We're not sure when these will take place, but will happen between 00:30 and 02:00 and will happen over three nights. This will cause 'blips' for many customers - lines will drop and reconnect within seconds or a couple of minutes.
We would usually be able mitigate any disruption by cleaning moving our traffic off the affected links. However, at the moment BT have not specified which link and the date that this work will happen. Thanks BT!