The club and Milburn are in dispute with the 19-year old keen to leave Haven. A tribunal is set to take place on April 11.
Milburn joined Whitehaven in 2014 but a knee injury kept him sidelined for that season. He played one game for Haven in 2015 but was then released to his former club Kells.
It is has been reported that agreement was put in place for him to rejoin Whitehaven in December last year.
It is believed that Milburn has stopped training with the club, and has not been paid by Haven for some time, but the club has stopped him playing for another side.