That could potentially be very bad news. Just going by what you stated - TalkTalk said that they could only give you ADSL2+ speeds if you gave them the line rental as well. The primary reason for that is that they do not offer broadband only packages. The concern is that they may only have full MPF LLU in your exchange i.e. only capable of delivering both voice and broadband (as opposed to shared MPF (SMPF) which can be used by LLU operators to provide broadband on other telephony providers lines).
So I envisage two possible scenarios:
1. TalkTalk processed a sales order to take over both voice and broadband despite you indicating you did not want to proceed. That would cause your line to move from WLR with whatever provider you are with now to TalkTalk's full MPF. This would also generate a broadband cease that Zen would be able to see on their BT systems.
2. Both MPF and SMPF (or maybe just SMPF) capacity has been installed in your exchange by TalkTalk and as LLU is far less costly for them to supply they have migrated just your broadband from BTWholesale IPStream to SMPF LLU. This could be done without necessitating a move from Pipex (brand) to TalkTalk (brand) and still retaining your current telephony provider. The cease of the IPStream during the migration would also be visible to Zen in this scenario.
If scenario 1. were the case you should have received a "We're sorry you're leaving" letter from your current line rental provider. Check your post

It would also make it more tricky / expensive to move onto another provider for voice and/or broadband. Although you'd have a good case for recompense as they effectively "slammed" your line.
Personally I think that scenario 2. is more likely and it is in fact just coincidental timing that you called Pipex to discuss leaving and MAC codes etc. just at the time there were orders flowing through there internal systems to move you from IPStream to SMPF, so the agent quite possibly misinterpreted what they had in front of them. SMPF is no harder to migrate away from than IPStream - it uses the same MAC code process.
I've never been a customer of either company so can't comment on any customer service issues from my own experience. All I can say w.r.t. TalkTalk is from the comments made by posters on this forum is that the TalkTalk members' forum is often more expeditious than the telephone route in. Can't attest to the veracity of that, it's just hearsay.
Let us know how it goes - might be worth giving it a few days for internal sytems to sort themselves out then give Pipex a call back and confirm you are still active with them. They should also be able to confirm that they can see that you are now on LLU or not - although I think we know the answer to that already!
Edited by deleted (Fri 19-Aug-11 01:35:21)