@grolut, then that means, to answer Gekko's query, he will be charged sh3 for calling a ported 0733XX number from his Airtel number. Am I wrong?
3 things may likely make it an exercise in futility, with regards to the Kenyan market.
1. The fact that people have not been told their airtime will be lost when the number has been ported.
2. The fact that subcribers will not know when they are calling a ported number thus affecting their billing. Or even when they know, they will not call, 'Shucks, its not on airtel. That's 3 bob.'
3. Mpesa is big. Who wants to send money to a Safaricom number that has been ported to Airtel and pay the high charges of sending a number to an 'unregistered number'...
You know Kenyans, "Tunaomba serikal aiingilie kati..." I could be wrong though.
Luck is when Preparation meets Opportunity. ~ Lucius Annaeus Seneca