Be aware; Change from BT ADSL to VDSL on 19.07.1 release

BT changed me over from ADSL to VDSL this week.
I made at the appropriate changes in the network configuration , PPPoE, dsl0.101 etc etc.

I could not get it to work, kept getting NEGOTIATIONS_FAILURE message in the wan setup .
The physical VDSL settings seem ok, seeing a connection being made under the status window, but was not receiving any IP address sett for WAN connection.

After a lot of hair pulling and trail and error, I got it to work by adding a dummy password in the chaps credential settings. Looks like an empty password string does not work for BT in our exchange ( Ford in Scotland)

So if you can't get it to work, try adding a password to the setup under

config interface 'wan'
        option proto 'pppoe'
        option username ''
        option ipv6 '0'
        option ifname 'dsl0.101'
        option password 'test'

fwiw, known issue with BT. First documented in Jan 2019 in OpenWrt install guide for HH5A - see section 7.5

wiki page updated as it wasn't clear there was a 'space' character for BT password in VDSL config example.