If the assignment dates in the letter and contract disagree, any dependent travel or TD planning tied to those dates should wait until the discrepancy is resolved. Planning school start dates, travel, or housing around an unconfirmed date range risks conflicting with the corrected dates once the documents are reconciled.
Hold dependent planning until dates are confirmed
Avoid booking travel, arranging schooling, or finalizing dependent visa steps based on either the letter's or the contract's dates until the employer has confirmed and corrected the actual assignment period. Once the corrected documents are in hand, revisit dependent planning using the confirmed dates. This avoids a situation where the household commits to a schedule that no longer matches the corrected employer documentation.
There is a further reason to wait. Dependents are admitted in TD status, which does not carry work authorization, so a spouse who intends to work in the United States needs a separate basis with its own timeline. If the corrected dates move the principal's start, they also move the point at which that separate question becomes urgent.
Write out for the household which commitments actually depend on the confirmed dates, such as school registration, a lease commencement or a notice period at a current employer, and which do not depend on them at all. The list is usually short, and setting it down converts an anxious wait into a small number of decisions that can be taken quickly once the corrected documents arrive.