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[licquorice]

Probably simply due to the reset causing a change of public IP address.

[Paul608085]

@licquorice 

I tried re-powering my router a few days ago to test for that.

The public IP address that I had when I first experienced the issue, after re-powering and also now after the factory reset, are all in the same range - ie the first three octets are identical, only the last three digits have been changing.

[licquorice]

So it changed.

IP addresses are logical not physical. The routing from sequential IP addresses could be totally different.