My two cents, I think maybe youve missed the boat this year, the contact tenders with the BofEs will be sown up by arseholes like siad company by now, but its still worth looking around, the jobs advertised at the mo are highly likely to be replacement positions for teachers droping there contracts, A company I worked for at one point lost there local city contract where I was because they had a huge teacher turn over and ended up unable to fill the positions they'd tendered for! thats where it would be good to get in direct as they would be getting desperate. My situation was I worked for the contracting company then was asked to stay on by the teachers who were going to approach the board for a direct contract but I'd had enough of being a meat puppet by that stage. As far as interac goes I only heard the same as everyone else, But couldnt be too bad to tide you over? I have no first hand experience with them.
The best thing to do would be to aproach private schools, they often employ direct, tend to do things on a whim, ie alot less rigid burocracy to deal with, give you a degree of autonomy in the classroom, better pay and full pay holidays. Thats where Id be looking. especially if you have some good experience to back you up.