Do you normally call your local immigration office before the designated date on your under consideration stamp or show up on the day. I called CW and they said I must go on the day stamped in my passport, but others on Thai Visa say they usually call to see if the result is in yet and if so go ahead of time.
TLDR : Answer Summary
It is generally recommended to go to the immigration office on the date stamped in your passport for the under consideration status. While some might call ahead to check on their application status, especially at smaller satellite offices, the main office (Chaengwattana) suggests that showing up on the stipulated date is standard practice.