Gymns became the final team to qualify for the Warehouse Fitness Floodlit Cup semi-finals on Sunday.
A goal in each half from Kayleigh Whitehead booked their place at the expense of Colby in a 2-1 win.
The southerners, who only needed a draw to qualify, replied through debutant Sarah Wignall.
FC Isle of Man launches women's team
"We want to create opportunities" says club chairman
Rugby: Vagabonds beaten at home in challenging conditions
Manx sides affected by Storm Boelo
Football: Castletown win on storm disrupted Saturday
Only one fixture was played due to Storm Boelo
Boxing: Jade Burden loses to Shauna Browne
Manx fighter beaten after sixth-round stoppage