It’s one of a number of new regulations proposed by the Competitions Working Group which were approved by the SPFL Board this week. In previous seasons, participation of Colt teams was limited to U20 level.
In a further change to the competition, which recently welcomed Sutton United and Boreham Wood from the English National League, all games up to and including the quarter-finals will go straight to penalties rather than extra time if level after 90 minutes.
SPFL Chief Executive Neil Doncaster said: “Since the new format was introduced, the IRN-BRU Cup has proven to be extremely popular among fans, players and clubs, and we’ve continued to innovate and evolve the competition.
“We believe these rule changes, together with the introduction of English clubs, will make the IRN-BRU Cup even more exciting for supporters.”
First-round ties will be played on Tuesday/Wednesday August 14/15.