O2 last week added BlackBerry Unlimited to its range of free bolt-on offers for customers signing to 18 or 24 months contracts.
However the network is refusing to allow customers who currently already pay for the service to switch to the free offer.
New and existing O2 customers signing for the O2 600 tariff or above on 18 or 24 month contracts are entitled to one free unlimited bolt-on, which they can swap every three months. This previously only included non-Blackberry data.
This meant previous customers wishing to take a BlackBerry on contract and use it for internet and email were required to pay £10 extra per month for an unlimited service. They can only switch to the free offer at the end of their contract.
O2 staff said they were expecting complaints from customers paying the fee whilst new customers can take it for free.
An O2 staffer said: “When people sign up for the BlackBerry they begrudge paying the extra £10 for the unlimited service and nine out of ten people will ask if they can have the service as their free bolt-on rather than pay, which until now they couldn’t .”
Another O2 staffer said: “They shouldn’t have waited until now to include it, a lot of people will be spending more money just because of the time they purchased it, which isn’t right.
“When those people find out about this they will want to change it but they cant. It’s not really fair.”
An O2 spokesperson said. “This is a new bolt-on that we have just launched in retail and in our contact centres.
"Existing customers will be able to take advantage of this offer when they are eligible for an upgrade."