What tax benefits would Harry & Meghan get & what would they lose on UK return?

Prince Harry and Meghan Markle, whose collective fortune is $60 million, would lose out on four years of Foreign Income and Gains (FIG) and inheritance tax advantages upon returning to UK after six years. They would have reaped benefits had they returned after 10 years. However, under temporary non-residence rule, assets they sold while living in US won't be taxed.