HGA won the Home Group contract in October following a competitive pitch to organise eight 500-delegate events.
The events, which will be held in two venues in the North and Midlands in April, aim to communicate business plans to the 4,000 employees.
Brakes has also appointed the agency to run a series of six-monthly events for its senior management team.
Following roadshow events in Glasgow, Tamworth, London, Ashford, Runcorn and Bristol in May, HGA will deliver an event at the Coventry Hilton in the second week of November to deliver a strategy update to 350 staff.
"This time they wanted to bring everyone together in one location, but next May they will probably do another roadshow," said HGA Creative Communications live events director Ian Grime.