Tension on a SMT joint at the Solder wave process

Currently, I am having problems with a AMP Mictor connector at the wave process. These connectors have both SMT leads(topside) and thru-hole leads.

Even though we have re-designed the board for via issues. We still see some of the SMT leads re-flow and fracture at the wave process.

The profiles that we have run(numerous) all show that we are well below reflow temps.

I feel that the problem is related to the amount of twist/bow that the board encounters when goes over the wave. The board is quite large - plus 15" in width.

Can tension/stress on a component cause it to reflow at temperatures under normal reflow temperatures?

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