Several ZDNet UK readers have complained that they have encountered setbacks when they tried to claim their free economy flight to one of eleven destinations in Europe and the US.
Some say that they were told they weren't able to get flights to the destination of their choice, even though this should have been possible under the terms and conditions of the offer. Others have reported that they have struggled to get any details about the state of their applications.
BT has admitted that some people have encountered difficulties getting their flights. A BT spokesman said on Friday that this was "less than 1 percent" of those who applied, which he said equated to "hundreds" of people.
BT is adamant that the problem isn't on the scale of Hoover's, whose offer in the early 90s of a free flight to America with every purchase worth £100 or more went badly wrong.
But Harry Cichy, who led the fight against Hoover, believes BT could be facing big problems.
Cichy told ZDNet UK that he has been contacted by a significant number of BT customers complaining of problems. He believes that the issue will snowball over the next few weeks.
"There should be more control on free flight offers," said Cichy.
"I was very surprised that a company of BT's pedigree should go to the level of offering free flights to sell its broadband," Cichy added.
There has been concern in the advertising industry about BT's offer.
"We've heard rumours of the promotion going off the rails," said a spokesman for the Institute of Sales Promotion (ISP). He added that ISP had not received any official complaints and wasn't treating it as a significant issue at this stage.
The Advertising Standards Authority (ASA) has already received one complaint from a BT customer who claims to have encountered problems with the offer. This complaint is currently being investigated by the ASA.
BT insists that everyone who is entitled to a free flight will get one, and blames the "extreme popularity" of its offer for the hundreds of people who have been hit with problems.
But according to Cichy, one factor is that the travel company handling BT's offer is also processing a similar offer from Sainsbury's, and is struggling to cope.
This company, called Rise Travel, had not returned requests for comment at the time of writing.
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