My module development snapshot is never updated I made some changes to my module on Drupal.org and pushed them up; I have seen that Drupal.org updated the development snapshot. Shortly after, I made some more changes and pushed them up, but this time it has not been updated.

I do see my commit when I look at View commits.

I was told that Drupal.org updates the development snapshots every 12 hours; but it has been already 24 hours since the last git push I did.  

git push origin 7.x-1.x
Everything up-to-date
Drupal.org shows a link to your drupal.org account for each commit you do only when Git has been set to use the same email associated to your drupal.org account.
If the email you are using with Git is different from the email you are using to get emails about your drupal.org account, you can add that email on https://www.drupal.org/user/1327432/edit/email-addresses. In this way, the commits you do for a module are associated to your drupal.org account which also means, for example, that the Maintainers for Slack to Drupal block that appears on https://www.drupal.org/project/slack_to_drupal show the exact number of commits you did and when.



The new email associated to the drupal.org account doesn't need to be made the default one, which means it would be used for every communication from Drupal.org. It just needs to be added to your account, so drupal.org associate the email to an account.
For the other commits to be associated to your account, you need to open an issue on the Drupal.org infrastructure queue asking to associate your commits to your account, similar to Request to associate commits with my account.