https://docs.github.com/en/rest/migrations/orgs#start-an-org...
https://docs.github.com/en/rest/migrations/orgs#download-an-...
Using a Github App you get 15K requests per hour. Even with pagination(100 records per request) you should be able to get at all of this data within a couple of hours. I suspect you lack reliable transformation tools to take github metadata and convert it to gitea versus the limitations of GitHub.
Although as I have run the migration myself several times to attempt to debug issues, it takes over 24hours due to ratelimiting.
Disclaimer: I'm one of the members of the technical oversight committee of the Gitea project, and am employed to work on Gitea.
"Keep these ideas in mind when creating GitHub Apps:
- A user or organization can own up to 100 GitHub Apps."
https://docs.github.com/en/developers/apps/getting-started-w...Which is 1.5 million API requests per org per hour.
How many committees are there and how many people on each committee?
The reason to say it as a disclaimer is because we are going to have some bias.