The 15-year-old, at her final attempt, was 0.03 seconds inside the Olympic qualifying time for the 400 metre individual medley at the weekend after touching home a personal best time of five minutes 1.33 seconds.
The mark was also a new Island Junior record, previously held by Dias.
AIB Tigers head coach Nathan Jégou said: ‘Ella travelled to Portsmouth on her own; it was a fantastic swim because she had to do all the work herself and she finished 20 seconds ahead of her nearest rival.
‘This is reward for all the very hard training put in over Christmas, the only day off was Christmas Day but the rewards are great.’
Dias will join club colleagues Emily Bashforth and Gio Guarino at the trials while Jerseyman Tom Gallichan, who qualified while training with Tigers last year, will be representing his current Liverpool swim club.
