However, people on here who say 'a contract's a contract's a contract's a contract' need to spend some time with the ALI Restatement of Contracts, and some case law.
If party A makes a mistake in the written contract, like in price, and party B knows it or has reason to believe it, then party B can't sign the contract and take advantage of it.
That's generally the law, and that's ethical.
My point is that once you have messed up, an organization is smart to be aggressive and disclosing in terms of damage control. When mid-level managers present you with a bowl of lemons an enlightened boss starts passing out lemonade.