| Date | Event | Comments |
| (varies with participant) | Proposal deadline | Proposals received by National Gemini Offices (NGOs). |
| Late April/Early May (set by participant) | NTAC meetings | Scientific assessments by each Gemini participant ("National TAC"). |
| 14 May 2021 | E-transmission | Electronic transmission of NTACs results to Gemini. |
| 1 June 2021 | ITAC | International Time Allocation Committee meets to resolve issues and recommend programs. |
| 15 June 2021 | 21B schedule and Phase IIs available | 2021B OT templates available to successful PIs. |
| 1 July 2021 | Phase II reviews start | The response time is 7 days for checking from "For Review" and from "For Activation". |
| 15 July 2021 | Phase II deadline | Mandatory for all PIs (earlier submission is encouraged). |
| 1 August 2021 | Start of semester 2021B | 2021B programs may be observed earlier to fill queue nights. |