BT moved all 40/10s to 55/10 eighteen months ago, if their lines warranted it. I don't think that is anything to do with this PLusnet change..
I would say that with Plusnet having been positioned to fight TalkTalk, it hasn't had a chance since TT moved from 40/2 to 40/10 earlier this year. In my opinion that is a far more likely reason than what BT is doing.
BT isn't changing Infinity 1 at the moment. It seems it is upgrading selected longer-term customers to 80/20 and no price increased. Basically a voluntary same-price retention deal speed upgrade for those that can get it.
It is still selling Infinity 1 with no price change.
My broadband basic info/help site -
www.robertos.me.uk. Domains, site and mail hosting -
Tsohost.
Connection - AAISP Home::1 80/20. 200GB. Sync 73724/12601Kbps @ 600m. BQMs -
IPv4 &
IPv6