Hopefully rap this up quickly.
Except I've seen somewhere that Tomiyasu is likely to be selected for the Japanese team for the Tokyo Olympics, which end around August 8th.
So, once you factor in any Covid-19 isolation period travelling to the UK, he'd miss all of pre-season.
Since Tomiyasu will also be adapting to a new league, he probably won't be up to speed until mid to late autumn.