trevHCS:
I would skip the agency and go direct to employer yelling them you’ve heard on the grapevine theres a vacancy.
Oh, I see… that’s where I went wrong! If you want a full time job, ring the gaffer and yell at them! 
“HELLO ITS JOHN FROM A FEW WEEKS BACK! IVE HEARD THAT YOU HAVE A FULL TIME JOB”
Sorry, when I read that, I was in hysterics!