How long does it take for a consulting engineer to change his major?

It takes 20 days for a consulting engineer to change his major. According to relevant public information, it takes 20 days for consulting engineers to change their registration and apply for the initial registration certificate. According to the relevant regulations, the registration preliminary examination organ shall complete the examination within 20 days from the date of accepting the application, and report the application materials and preliminary examination opinions to the competent construction department of the State Council, and the registration organ shall make a decision within 20 days from the date of accepting the application.