gbotley you are pretty much spot on.
Flexi contract is £33/hour until 500 and then £43/hour (scheduled block hour)
take home during the summer doing 90hours/month was £2.3-3.5k average depending on hourly rate (based at LTN)
Salary works out to approx £33-35k for first year, then after a successful temp to perm interview, £41,320 SO contract. I've just finished 13 months on flexi so these are up to date figures.