Lovefilm 6 months for £10

[#1]

I already have a Lovefilm account and was wondering if i can offset the £10 for 6 voucher against my normal payments.
It does not say in the letter its for new customers only and on speaking to a spectacularly unhelpful person at Lovefilm was told it was only for new customers.
If this is "gift for pklusnet unlimited customers"  as per the letter-why not???
Thank you for your help.

[#2]

I've just dug out a copy of the letter, in the terms and conditions it says the following:

Quote

Terms and Conditions: Offer expires on 23/08/2013. This offer entitles you to 6 months for £10 LOVEFiLM Instant. 18+. Paid subscription starts automatically after offer period unless cancelled (and any discs returned). One package change, but no address change, allowed during trial. Minimum recommended line speed 2meg. New LOVEFiLM customers only. Not redeemable in conjunction with any other offer. One per household. All information correct at the time of print and subject to change or withdrawal by LOVEFiLM without notice. Full terms of Lovefilm service at lovefilm.com/terms. © 2013 Amazon, Inc. or its affiliates. Content is streamed over internet. Excludes pay per view services. Streaming on Xbox 360® requires Xbox 360® LIVE Gold. Exclusive titles not available on other UK subscription streaming service. By invitation only. Available on Plusnet Unlimited only.

[#3]

Whoops -ok noted many thanks and sorry not to have seen that in the letter.
Regards

[#4]

Hi ,
we have received a letter from PlusNet with this offer, only problem is when we go to the lovefilm site it only offers £5.99 a month. How do we get the £10 6 month deal?
Thanks

[#5]

Does the letter provide a special code to be entered on sign-up? Or a special sign-up page link?

[#6]

The letter should say that you'll get the offer code within 10 days of upgrading to Unlimited with us. Have you done that?