How can system improved if one arrive at the probability of availability of free lines during the busy hour?

Improvement can be made when the system is act as a loss system in place of a delayed system. Within a loss system, the caller has to repeat a call till the call is maintained. It reduces the delay by releasing a caller from the queue till there is repeated action.

Blocking probability can be helpful. This blocking probability P is described as the probability that all the servers are busy in system. When in system all the servers are busy, no additional traffic can be carried through the system and the arriving subscriber's traffic is blocked. At same instance, this may appear that the blocking probability is similar measure as the GOS. The possibility that all the servers are busy may well signify the fraction of the calls lost that is what the GOS is all about.