Starts: Friday, 27 July
Nieland has been injured and did not make the qualifying mark
Ends: Sunday, 29 July
Venue: Manchester Regional Arena
Live coverage on BBC One (Sat: 1635-1755 BST) and BBC Two (Sun: 1715-1930) and Radio Five Live (Saturday from 1300 and Sunday from 1500).
The national championships got under way on Friday with Britain's leading athletes looking to secure their places in August's World Championships.
Nick Nieland won the men's javelin with a throw of 73.95m, which was well outside the standard for the Worlds.
Andrew Lemoncello took the 3,000m steeplechase in eight minutes 42.57 seconds while Nadia Williams won the triple jump with a leap of 13.58m.
The World Championships take place in Japan from 25 August to 2 September.
The men's 400m heats also began on Friday, with Andy Steele strolling to victory in 47.46s.
Martyn Rooney posted the fastest time of the night with 46.74sec, while Robert Tobin won his heat in 47.16sec.
The British team for the World Championships could be the smallest ever because of the stringent selection policy that has been adopted by UK Athletics performance director Dave Collins.
"The policy is part of a more focused approach to selection with the emphasis on consistency of performance and the enhanced development of our emerging talent," said Collins.
UKA's new chief executive Nils de Vos has set a target for Osaka of 14 finalists and three medals.