Perhaps the next time a Rishworth solicitation email is received, rather than be deleted, it may be replied to accordingly:-
I am aware that Rishworth is currently withholding an amount of salary payments to some pilots, contrary to their mutually agreed contract terms and conditions. There is a risk you may also unilaterally amend any contract I might sign, you will understand therefore, why I am unable to enter into any business relationship with your agency at the present time.
Please feel free to contact me with further opportunities at such time your agency acts in an honorable, professional and businesslike manner.
After a few hundred replies like that, they may think twice before breaching a contract.
