Based on my experience in HR, it is reasonable to follow up with the hiring manager or HR representative regarding the status of your job interview. It shows your interest and enthusiasm for the position. However, I would recommend waiting for at least a week after the expected follow-up date before reaching out, as it allows the hiring team enough time to review all candidates and make their decision. When you do follow up, be professional and polite in your inquiry, and ask for an updated timeline. This will help you plan your job search accordingly. Good luck!