At MTT now. Got a stamp corrections from oct 26th (got extensions via embassy letter prior to latest amnesty). Required 1 copy of the data page of my passport and had an appointment. That's it. Crossed out 26th and replaced with Nov 30th. Took about 90 min maybe 2 hours of waiting.
TLDR : Answer Summary
The user reports visiting the MTT for a stamp correction on their visa, where they changed the date from October 26th to November 30th. The required documentation included a copy of the passport's data page and having an appointment. The process took about 90 minutes to 2 hours of waiting.