Welcome to the forums.
Some standard info below, Would need staff to confirm that they are happy to set up as it is a house move too which complicates things.
First you must be an existing Plusnet broadband customer.
Then, check with BT if you are able to get FTTP using the BT Broadband checker at http://www.dslchecker.bt.com/adsl/adslchecker.welcome?
The results will need to look like this
If the first line of the "Featured Products" says "WBC FTTP" then you can apply for the trial at http://trials.plus.net/
Another way is to go to the BT Retail website and see if you can buy Infinity 4 from them (FTTP at 330Mbps download). If you can then you can also apply to join the Plusnet trial or use BT or even Zen (the latter 2 offer FTTP as a product not just a trial)
Finally Plusnet only offer 2 speeds for FTTP, 40Mbps down/2Mbps up or 80Mbps down/20Mbps up. Use BT if you want faster.
Ex - Plusnet Customer (2009 - 2023) now with BT