We are getting this feature request from WorlogPRO customers from time to time. This can actually be done using issue subscription and JQL feature of Jira so we have decided not to implement this. Instead of implementing it we will document how it can be done. Lets assume that you want to be notified in the following condition:

• Issues time spent is 90 percent of original estimate for the issue
• Issue is still not resolved
• We want notification to be as fast as possible, that is we want to be notified just after user log work on the issue

Create a Jira filter

resolution is EMPTY and workratio > 90 and update > -5m

Here we are searching for non-resolved issues with time spent is at least 90 percent of original estimate and updated within last 5 minutes. Here update > -5m is critical part of query. Logging work for an issue makes that issue updated. If we don't add update > -5m clause, JQL will find the same issues whether work logged for them or not again and again. 

Save the Filter

Save filter with any name you want.

Create a subscription for the above filter

Create a subscription for the filter and select CRON expression mode. This is required to send notifications with 5 minutes intervals. Enter the following CRON expression.

*/5 * * * *

This expression will cause filter to be executed at every 5 minutes and will send notification email for matched issues.