I am a manager and have had some instances of starting late and leaving early over the past 3 months. I did not inform my manager on all occasions, but did inform my staff. I have been employed at this company for 2 1/2 years and have never received a warning. I am now facing a disciplinary hearing, could I be fired?

My manager had an informal discussion with me regarding this matter but has not issued warnings, this hearing will be the first formal action he is taking.