Josh signed a two-year deal at Spotland in May to start his third spell with the club.
The goalkeeper first joined Dale on an emergency loan from Scunthorpe in October 2009, playing in a 4-0 win at Bournemouth, before returning to Spotland for the first half of the 2010/11 campaign.
The son of former Derby and Manchester City player Mark Lillis, Josh went back to Scunthorpe at the end of his loan spell, but found his chances limited at Glanford Park and left the club this summer.
Aged 25, he also played on loan at Notts County and Grimsby during his time with The Iron.