Can they revoke a job offer once you've started?

[GertiesEyebrow]

If you are given a provisional job offer subject to checks and references but at the company's insistence HAVE to start the job before they get those back, can the company then dismiss you if they aren't happy with them?

Yes, you can be dismissed for any non-discriminatory reason in the first 2 years of employment.

Yep

Yes