Tusker's decision to withdraw means they will focus on the league duties uninterrupted as they hope to seal the championship for the first time since 2016.
Consequently, the Cecafa competitions committee had to reshuffle the programme to change the groupings, which now places four teams in each of the two groups.
Ugandan Premier League champions Express FC - the country's representatives in the Caf Champions League next season - will begin their campaign against Atlabara FC of South Sudan on August 1 before Tanzania's Yanga SC - who will also participate in the continent's premier club competition - face Nyasa Big Bullets of Malawi, who were invited to the tournament, and both games will be played at the Benjamin Mkapa Stadium.