articleship term

sir,

i want to know that till when i have to go for my articleship for my nov'08 pcc attempt, if i was registered on 26th of april'07?

would my casual leaves would be deducted from 15th month compulsary practicle training?

if i go for only 1 group in nov and then do for 2nd in may what will happen to my articleship term?

after my nov attempt my articleship will resume from 15th month or 18th month?