Boeing Background Check - 30 Days??

Hi. I was ordered an "Employment Verification Plus" background check for a new Boeing job. It is an up-to 30 business days background check where the third-party verifier must spend 30 business days trying to contact a previous employer directly. Only once the 30 business days are up will they then use my W2 if they couldn't reach my previous employer.

Has anyone had this experience with a Boeing background check?

The 30 days will definitely run over my projected start date from the CJO.