How to purge / modify time tracking in bulk mode

[Gregory Demotchkine]

Recently due to testing different addins, I had about a 300 issues that have original estimate and remaining estimate set to 2 days. This is a disaster and

a) I learned sadly that we cannot purge/modify time tracking via bulk change

b) I tried tricking with a worklow transition using a Post function that purges the 3 time tracking fields, but that does not work at all, it doesn't affect anything.

Any ideas how I can reset these 300 issues ?

Original issue for what happened:

https://answers.atlassian.com/questions/214570/time-estimation-is-automatically-set-to-2-days-for-multiple-issues

[BenP]

You can add a workflow post function to clear the time tracking field, e.g. when an issue is transitioned into the Resolved state.