Extra usage allowance confusion

[#1]

Just wanted to provide some feedback to Plusnet regarding the issue I had today for the extra usage cap.
I'm on the 60g monthly contract, and the other day I saw that my maximum usage was set to 70p for some bizzare reason, so went ahead to click the "REMOVE" button as I did'nt want to go over the 60g allowance.
Today I received an email saying that I will be charged £5 for going over this, when I spoke to the customer service lady on the phone she explained to me rather rudely that I should of set the limit to £11.49 (equal to the monthly rental cost) which ensures that I won't be charged in the future for going over the limit.
I quickly checked the T&C's online and found this is NOT the case so bad advice for a start!
I called the customer service team and spoke to another lady she explained that the advice I was given over the phone previously was incorrect!
She explained that because I clicked on the "REMOVE" button that gets rid of the cap, I needed to set the limit £0.00 if I did'nt want to go over my usage limit this was'nt what I was told previously!
It would of been nice if it said on the screen clicking the "REMOVE" button gets rid of the usage cap to avoid possible confusion for others.
I must say Plusnet was kind enough to refund the extra £5 off my next bill as a good will gesture for this confusion, many thanks

[#2]

I must admit that hadn't occurred to me as the Remove button is next to the Maximum extra monthly spend and removing it removes the limit.
I agree though the first advice was a load of cobblers and the agent will need introducing to :mand:

[#3]

Hi leew88,
I'm sorry to hear that the support you received was rude. I have fed this back. I think the confusion with the advice comes from the fact that if a customer sets the cap via our website it is set at £0, whereas when we set it on your account we have to set it to the subscription charge, so If your package is £11.49 we have to set it at £11.49.
Jojo

[#4]

What about add-ons (e.g. Pro or Max Premium)? Are they included in the figure you have to set?