Van Blerk said: "My contract's up so you could say it's better to get me off the books and bring his own players in.
"I'm sure if there were a few more players in the same position, they would be leaving as well.
"When you are on a short-term contract, you are easy to get rid of but that's life.
"You move on to another club and hopefully I can do bigger and better things."
He is the fifth out-of-contract player not to have his contract renewed, with Theodore Whitmore, Ian Goodison, Rodney Rowe and Adrian Caceres leaving previously. No announcement has been made on 21-year-old Ben Morley, who signed a one-year deal last summer.