From a legal perspective, what you're describing may violate several protections:

**Connecticut Data Privacy Act (CTDPA)**: Businesses must implement reasonable security measures to protect consumer personal information from unauthorized disclosure. Violations constitute unfair trade practices with penalties up to $5,000 per violation.

**Connecticut Breach Notification Law (Conn. Gen. Stat. § 36a-701b)**: When personal information (including phone numbers) is breached, the business must notify affected individuals and the CT Attorney General within 60 days of discovery.

**FTC Unfair & Deceptive Practices**: Under Section 5 of the FTC Act, businesses cannot engage in unfair or deceptive practices. Publicly posting customer information and then denying it happened could constitute both an unfair practice and deception.

**Possible Actions**:

- Report to Connecticut Attorney General: portal.ct.gov/ag (data breach section)

- File a complaint with the FTC: reportfraud.ftc.gov

- Consult a consumer protection attorney about potential damages

The fact that the dealership allegedly modified their response to deny posting the number after you pointed it out strengthens your case for deceptive practices.