You will go onto Sky LLU, which is ADSL2+. (Not ADSL+2
Your ADSL problem was probably a fault on the exchange equipment, not the ADSL itself. The move to O2 connected you to theirs, not BT Wholesale's.
Sky also have their own equipment at your exchange so almost certainly nothing to worry about. There's always a slight risk of something going wrong of course, with any change to most things in the world.
If you are getting well above 4Mbps speed
on O2, don't worry if it drops to just under 4Mbps at first. That is how Sky handle their "line training". It will rise after a few days to the same sort of level you have now.
My broadband basic info/help site - www.robertos.me.uk
| Domains,site and mail hosting - Tsohost
Connection - Plusnet
UnLim Fibre (FTTC). Sync ~ 59.4/14.4Mbps @ 600m. - BQM
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- Jean-Antoine Petit-Senn.
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