The ads, "scary Mary", "quiz night" and "Sammy silage", were an attempt by Phones 4U to take on the market leader, Carphone Warehouse.
However, with the departure of the Phones 4U marketing director, Paul Hamburger, and half of the senior marketing team earlier this autumn, the campaign is in jeopardy.
It is now expected to ditch its branding investment to return to the price-led advertising it ran before hiring WCRS. John Caudwell, the company owner, is leading the move.
Phones 4U also announced this week that Jim Slater, the former Sunderland FC sales and marketing director, had been appointed as its marketing and customer relationships management director.
Phones 4U and WCRS were unavailable for comment.