Plus net unable to supply internet and want to charge me £155 to leave.
FIXED
Hi Jack,
A warm welcome to the forums. Is your new house a new build (only served by FTTP - no copper) or is it in an area not served by BT Openreach at all? Or is this a matter of you being on Fibre now, but there is no fibre availability at your new home, but ADSL is available?
Unfortunately Plusnet do not offer a get out of jail free option in the event that they cannot continue service at your new home...
https://www.plus.net/help/legal/terms/
9.3. If we can't provide any broadband service to your new home, you'll have to pay early termination charges as set out in the Price Guide.
Being forced to remain in contract or pay ETCs where a supplier can no longer supply could be considered to be an unreasonable unfair restriction and therefore might be unenforceable, but that would need to be tested by the courts / Ofcom. However the latter is pretty useless most of the time, as can be seen from this finding against Virgin Media in respect to people wanting to retain their contract but have moved to a non-served area...
Some consumers had also previously complained that it was unfair to charge them ETCs if they had Virgin Media and wished to retain the service but were moving to a new house that existed outside of the operator’s network area. Unfortunately Ofcom has today decided that this specific complaint “does not fall within the scope of GC 9.3,” although they are “continuing to consider whether these terms raise concerns … and we will provide an update in due course.”
Plusnet are not alone in operating this 'behaviour' - I suggest that a referral to Ofcom asking them to follow through on their May 2018 findings is long over due.
http://www.talktalk.co.uk/media/pdf/legal/TalkTalk_Customer_Terms_and_Conditions_v20180110.pdf
17.2 We’ll try our best to transfer the services but, if we can’t transfer some or all of them, and any are in the minimum period, you may have to pay the charges to the end of the minimum period.
https://www.sky.com/shop/__PDF/Sky_Broadband_Talk_UK.pdf
6.2 If you change your Address, this Contract will continue unless you exercise a right to end it under this Contract or we are unable to transfer your Sky Talk services to your new address. You will need to ensure that you have a working BT compatible line at your new address. We may charge you any costs we reasonably incur as a result of a transfer. We will tell you whether a charge applies and the amount before processing your move but you can also see whether we currently charge for transferring services at https://www.sky.com/help/articles/moving-home-faqs.
The Sky T&C is not completely clear if ETCs do or do not apply here - this condition follows the ETC conditions. It is clear that the contract will not continue if they cannot transfer the service, but I suggest remains ambiguous about ETCs.
http://www.vodafone.co.uk/terms-and-conditions/index.htm
7.5 (c) If we are unable, for any reason, to provide Home Broadband and Phone Services to your new address in the UK then you will be entitled to end this Agreement subject to provision by you of reasonable evidence of your change of address and payment by you of all charges owing up to the date that we disconnect your service. We reserve the right to apply any termination fees or charges. For more details, please see our Price Guide
Surprise of surprises BT Retail is very reasonable where they cannot provide service.
https://www.productsandservices.bt.com/products/static/terms/post3rdjuly2016voiceandbroadband.html
Charges for ending the agreement early
- You'll have to pay us a fee for ending the agreement early if:
- you end a service during the minimum term, except in the circumstances listed in clause 13c below; or
- we end a service during the minimum term, in line with clauses 11b(iii) to 11b(xii).
- Equipment: If you end a service during the minimum term and you haven't paid for any of the equipment in full, we may charge you the full price of the equipment (except in the circumstances listed in clause 13c). For example, this may happen if we've given you a home hub and you didn't pay the full price for it.
- You won't have to pay the fees and charges referred to in clauses 13a and 13b if:
- you end a service within the cooling-off period as shown in clause 10a;
- you end a service under clause 17b as a result of changes that significantly disadvantage you;
- you end a service under clause 10d as a result of us breaking a significant term of the agreement;
- you end a service under clause 10f as a result of faults with that service;
- you end the BT Broadband service under clause 10g as a result of consistently low broadband speeds;
- you end a service under clause 22a as a result of us moving you to another service; or
- you move home and we cannot provide a service at your new UK address.
You could always try asking for compensation from Plusnet under clause 13
13.1. If you let us know you've suffered an intermittent or continuous total loss of service we'll refund a pro-rata amount of any subscription fees you have paid in respect of that period of loss of service, except where:
but they might claim the MBORC get out of jail free - we accept no responsibility for anything card...
13.1.4. the failure is due to matters beyond our reasonable control
My personal position would be "I want to continue my agreement with you (Plusnet) but if you cannot fulfil that agreement then YOU default on the contract. However, in good grace, recognising your difficulty here, I will not pursue a claim for breach of contact if you agree to simply allow the contact to cease without penalty".
It would be very interesting to see how non-payment of ETCs in these circumstances plays out in court.
Judge: So let me make sure I clearly understand your case Mr ISP - you want the defendant to pay you for a service they told you they wanted, but you cannot supply? Are you for real here? 
