Fixed line prepaid system

I am working with a fixed line prepaid system for an operator.
the design parameters are as follows

Customers specify as follows:

Average Call Holding Time = 230 seconds
Subscriber base = 1,500,000
Busy Hour Call Attempt =30,000
therefore erlang/sub = 0.00128 (BCHA x ACHT)/(Subs x 3600)

Due to above specs, customer anticipate the following:

call/sec handled by system should be = 8.33 (BHCA/3600)
Concurrent Call Handling = 1,917 (ACHT x Call per Second)

Actual system performance are as follows:

ACHT (actually measured) = 411 second
Sub (actual readings from system) = 765,663
BHCA (actual readings at STP) = 20,000

From BHCA Calls per sec=5.56 (20000/3600)
Concurent calls = 2283 (5.56 x 411) ie ACHT x call per sec

To ensure system stability, we interim gapped the calls to 1000
concurrent calls. So calls per second=2.433 (1000/411) and resulting
in BHCA = 8759 (2.433 x 3600 or call per sec x 3600)

From the above, Can I say that the system is performing better then the
design criteria specified by the customer even when I call gapped
the system ?

Appreciate a second opinion from experts out there. Thanks