"We have given both Richard and Erdem free transfers to give them a chance to get fixed up with new clubs," Royle told the Club website.
"They are only 20 and are at a stage where they should be looking to push on and play first-team football.
"There are players here in front of them and giving the two lads free transfers now is better than at the end of the season when there will be many players available in the same situation.
"They are both great lads and we wish them all the best."