aleyro

So, it sounds like you have two "progression" nights, and relegate "farming" (i.e., kara) to another night in the week. Assuming that your going to keep up this schedule, I think you can make pretty good progress (actually, I'm banking on it; my guild has a similar raiding schedule).

Step 1: Move Gruul to your farming night, and spend 7 hours per week on Magtheridon, Void Reaver, or Luker Below.

Step 2: After about 6 weeks, you should have the 3 above mentioned bosses down. Devote 1 night to farming Gruul and those 3 bosses, and your second night to progression in SSC.

Step 3: After about another month, eliminate Gruul, Mag, and VR from your schedule, and focus exclusively on clearing SSC, devoting an entire night to Vashj.

Step 4: Once Vashj is down, move to 1 night ssc, 1 night eye.

Step 5: one night eye, one night Kael.

Step 6: Kael down, begin hyjal.

Basically, your (somewhat conservatively) looking at about 6 months before you reach t6 instances. This assumes a relatively stable core team of at least 20, with a few swingers coming and going. This also, obviously, doesn't take into account the impact of ZA from a scheduling/gear standpoint, or the any nerfs that significantly trivialize content.

If all goes perfectly, you'll be reaching Illidan about the time sunwell comes out, and be working through sunwell just as WotLK gets released (assuming pessimistic release times for both of those).