Work Visit Visa - First Travel Validity

Hi everyone, I have a query regarding the work visit visa. I'm from Dublin and I've been offered a position in KSU teaching English . The recruiter is EduGuide/Al Hussan Education and Training. They want to send me to Riyadh a.s.a.p. on a work visit visa and then transfer it to an Iqama at a later date postponing the medical and other procedural requirements. Is this common? Anyone experienced this?

I have asked to arrange my medical and Iqama prior to departure as I was advised about a fast track service they (EduGuide) use through London but I've been told that Irish candidates are precluded from this option, by the foreign office in KSA. Are there any Irish people who have possibly experienced something similar? Or any other expats with Irish friends/colleagues that may be able to shed some light?

Thanks in advance

P