Petcha Raheem I don’t see why an umbrella would make any sense for Littler. Umbrellas are for contractors who have predictable earnings for a fixed period and want a hassle-free system for accessing taxed income as rapidly as possible.
Freelancers who have outgrown sole trader status, with less predictable earnings and detailed costs, would normally just manage their own limited company and pay themselves, taking dividends periodically under advice from their accountant.
Littler has extremely unpredictable earnings, is at high risk of HMRC scrutiny, and needs specialised tax planning advice. An umbrella would be useless. He needs an accountant with experience of working with high profile sportspeople or entertainers, and one who is independent from Littler’s management and sponsorship team, as their interests in revenue recognition and cost control may diverge from his. At least he has an advantage over other young sportspeople in being demonstrably numerate.