So did you decline to accept this position?

If vacation pay and other benefits are important to you, I’d tell them I need more time to talk to a lawyer and to re negotiate my contract. It also depends on your circumstances. If you need a job to survive ASAP or if you can wait for something better etc

generally I’d not sign a contract that says I was given an opportunity when clearly I wasn’t given an opportunity at 4pm before the weekend. Sounds shady to me