For  Gold and Platinum health plans the medicines will not be sent directly for 6 months or a year but will be sent for a period of 3-4 months initially so as to monitor the progress of the patient  for better treatment results and then after analysis further set of medicines will be sent.
For availing  the discounted rates as above for Silver,Gold or Platinum plans,the patient needs to make the payment only initially before starting the treatment,it will not be adjusted later during the course of the treatment.
You do not need to pay extra charges for couriers anywhere in India,it is included in the health plan.Secondly a patient can avail treatment for multiple problems together.You do not need to pay extra for it,it is covered in the health plan.