It seems highly unlikely (sadly) that C4 will make a late change and forgo their F1 coverage in favour of the cricket. However, if they do that's where I'll be - either side of one tennis match.
A quick Google search has answered my own question...
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Channel 4 will show Sky's cricket coverage from 09:00 BST before coverage moves to More 4 at 13:15 while the British Grand Prix airs on Channel 4. The cricket then returns to Channel 4 after the race. https://www.bbc.co.uk/sport/cricket/48957255
