In Day 2 of the GB Aquatics Swimming Championships, Oliver competed in the 100m Backstroke event. He entered the event as the top seed, looking to defend his 100m Backstroke British title from last year. In the heats, Oliver was alongside Commonwealth Champion Brodie Williams and Olympic Bronze Medallist Luke Greenbank. Oliver stormed home to a new personal best of 52.87, making that his first outing sub-53 seconds and also moving himself past Olympian Chris Walker-Hebborn into number 2 all-time GB. NCAA college breakout Jonathon Marshall was closely following in 2nd place after the heats with a time of 53.47.

Oliver returned in the final to punch his ticket to the Paris Olympic Games with a winning time of 52.70. That mark also breaks Liam Tancock's British Record by 0.03. Oliver was closely followed by Jonathon Marshall who touched home in a 53.03.