Thanks for all the shared numbers, I've passed those on and am pressing Three for answers. They seem to be slowly getting to the bottom of this so we'll soon see what they come back with.
So relieved to see that it's not just me going through this issue, have been getting this issue on and off for about 2/3 months now. Hopefully something will be done now I've made a complaint and demanded a solution. It's been a massive runaround, contacting XBOX support and Huawei Support as Three stated every time it was their fault, only to find out it was Three's fault all along.
A three handset (iPhone 8) does not show any issues.
Are you using the 535 or another router?I’d leave but as it’s only £14/month for unlimited data including the device it’s too cheap to move away as any other provider would be at least double