[Spoom]

Two guesses:

1. One part of the company isn't talking to the other. One person wrote the offer letter and another wrote the contract, or the contract is "standard" and hasn't been updated for your particular case.

2. The company is intentionally trying to get you to accept less now with vague, nonbinding promises to make up the difference later.

I would guess that the first is probably more accurate. Keep pushing to get the offer letter terms into your contract. You'll find out soon enough if they refuse.

This lack of communication might be a red flag on its own, of course.

[le-mark]

Also 1, Hanlon's Razor. I've seen things such as the HR person editing an older version and failing to update with correct values. In that case it was simply "that's not quite right" to resolve the discrepancy.