Wheldon leaves at end of March after career spanning 37 years in advertising and marketing.
It is first government reshuffle since Boris Johnson won election in December.
Show is marking 60th anniversary later this year.
Campaign reported in December that about 9% of group's estimated 4,000 UK staff 'may be impacted'.
He is tasked with getting the agency back to growth
Creative Equals research shows only 12% of women of colour are in senior roles in adland.
Who Wot Why is not repitching.
Ad revenue for company dropped 5% year on year.
Rajar figures also show growth in speech radio, with LBC up 23.3%.
Change is intended to make it easier for listeners to absorb and recall information.
It will use technology, innovation and digital skills in football communities to help change lives of players, coaches and fans.
Deal was brokered by the7stars.
Spokesman said claims are 'unfounded'.
Review is part of plans to 'diversify' revenue streams.
Correlation between media usage of 16- to 34-year-olds and those over 55 has fallen by more than half since 2015.
Ad ran with tagline: 'Your paper's getting cleaner. Now what about your money?'
Business also includes Gala Spins brand.
Broadcaster will offer the competition winner a free ad spot during the final.
Agency will help build the brand across 40 markets.
The network is currently searching for a successor.