For the past week or so EE 4G appears to be introducing a 200 m/s delay about once every 2 minutes. I have seen this previously about two months ago when 1000 eyes identified a switch within ee was flapping and the resultant rerouting was causing disconnects to my virtual desktop at work. It looks like this was previously resolved but has now reappeared. I have a 5G unlimited sim using an Archer router plus 4G sim on EE mini Wifi Block and both exhibit the same issue. This is not location dependant as have seen this behaviour on the same day in Cornwall and Sussex yesterday (house move). Where do I formally raise this as a fault as it is currently unworkable. My physical broadband line does not exhibit the same behaviour.
The best way to report this issue would be to call EE C/S on 150 and speak to a second-line tech agent.
This may mean explaining your issue to the agent who initially answers, however there isn't any account access or formal fault reporting via this forum.
