There is a cease charge that Openreach levy for disconnection of broadband, as opposed to migration. I believe most ISPs pass on some or all of that charge. (Openreach also charge for migration but the gaining ISP generally absorbs that to get the customer).
What Plusnet haven't quoted you there is the phone line costs. I think (as long as you are out of any minimum term with your supplier) that termination costs nothing. But coming back to an Openreach landline service will involve a phone connection charge unless you find a deal at the time.
Virgin Media does not use your Openreach landline.
My broadband basic info/help site - www.robertos.me.uk
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Connection - Plusnet
UnLim Fibre (FTTC). Sync ~ 56.4/14.5Mbps @ 600m. - IPv4BQM
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- G K Chesterton.
Edited by RobertoS (Mon 10-Nov-14 22:02:14)