I'm in south Lincolnshire, fibre cabinet is connected back to the Sleaford exchange.
My girlfriend who is with Plusnet and connected to the exact same cabinet as I am has had no such problems, her vdsl connection was rock solid at the times I was suffering.
I'm currently unsure if it's Zen or my own router causing the issue, I have a cable router connected to a BT modem.
I've noticed since Monday my router is still disconnecting and reconnecting on a regular basis, it last did it around 7am this morning. So I've ordered a brand new router and going to see how that goes before going back to Zen.