The publicly owned delivery service agreed to a four year deal for “strategic communications”.
It was around the time many sub-postmasters launched High Court action in March last year.
One Horizon victim, former sub-postmistress from West Byfleet, Seema Misra, was sentenced to 15 months in jail in 2010 while pregnant.
Critics say the money should have been spent on re-dress for victims and their families.
