Some time you don't want everyone to know exactly when you committed. This command will wipe the time stamps and set them all to today at 0:00h.

git filter-branch --env-filter '
  GIT_AUTHOR_DATE="$(date +%Y-%m-%d) 00:00:00+0000"
  GIT_COMMITTER_DATE="$(date +%Y-%m-%d) 00:00:00+0000"
  ' -- --all

It works best on fresh repos just be for pushing to remote for the first timee.

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