Following question from Lehmann sample test states #4 as the answer. #1 is what i thought as the answer. Can someone explain how? thanks!!

A prime contractor in a customer project under CPFF contract has run into unexpected technical problems. Fixing them will require a lot of additional work to be done.

The company made a decision to book more staff and equipment from their subcontractors in order to adhere to the agreed timeline. The customer agreed to this decision.

What will most likely happen?