Stress on PCB during ICT

Our company is going to use BGA(1.27mm pitch) But I have heard of troubles with P-BGA. It is that cracks occured between solderball and gold plating of PCB during ICT(incircuit test). We know that gold plating of PWB is not good for BGA, so we decided to use solder plating PWB. But I think what matters most is the stress(bent or twist) on PCB during ICT. My question is 1.How should we measure the stress on PCB especially around BGA? 2.Is there any software to estimate stress on PCB?

Any suggestion would be appreciated.

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