The former Northern Ireland international had been on the transfer list since the end of last season after finishing the 2016-17 campaign on loan at Stevenage, and this development leaves the 28-year-old free to continue his career elsewhere after two-and-a-half years with the club.
Josh has spent most of the first half of this term on loan at National League side Torquay, but scored once for the Town in the Checkatrade Trophy draw with Tottenham U21s and then made another substitute’s appearance in the same competition against Peterborough last month after returning from Plainmoor.
The former Bournemouth and Millwall man departs with a Hatters record of eight goals in 45 appearances – and the best wishes for his future career from all at the club.