Issue with Group migration - Error 503 Backing off

Hi

We are migrating about 25K emails - and we have been able to migrate 2 out of 3 inboxes to google groups, using the migration API in GYB.

However, the third inbox is proving to be very tricky - with about 5K emails.

No matter what we are doing, it is just not working and finally we end up getting these errors:

Temp error 503. Backing off 16 seconds...attempt 5/10

Temp error 503. Backing off 32 seconds...attempt 6/10

Temp error 503. Backing off 60 seconds...attempt 7/10

Temp error 503. Backing off 60 seconds...attempt 8/10

using GYB latest version - but its just not working. We are very far away from the Quota limits - so there's no question of quota exhaustion - checked on the google cloud console - and it is verified.

Please help - any pointers on this would be greatly appreciated!

The issue names GYB's migration API workflow but no source file, entry point, or test. Start by reproducing the migration of the affected inbox and reviewing the 503 retry output alongside the Google Cloud Console quota information. Done means the cause is confirmed and the failure has a verified resolution or a clearly documented limitation.

Written by the indexing model from the issue text.