Allow two years worst case scenario mate. A year on singles you will get close to the tonne, then if your unlucky you'll get into a twin operator but push singles for another 3 - 6 months, or if your lucky you will get straight onto a twin. If you get good hours you will have 250 Multi within 6 months of being checked to line, and that will see you around the 1200TT mark with 250 multi and in bed with maybe Rex of QF link. If you hang on for the rest of the year you will have 500 multi command and around 1800TT. Stick to the 500 multi even if people are now advertising that you dont need it. Its money in the bank and patience is a virtue!
Good luck fella take you passion and make it happen!