Billy turned professional at the start of 2016.
He competed on the MENA Tour, EuroPro Tour, and Challenge Tour in his first year in the paid ranks.
He collected a first professional win at the Matchroom Sport Championship on the EuroPro Tour in June 2018, securing full playing rights for 2019 on the Challenge Tour.
Billy picked up a second victory at the Newmacher Golf Club Challenge in September and ended the season in the fourth spot on the EuroPro Tour Order of Merit, securing Challenge Tour status for 2019.