I want to build a report which shows who is current assignee of the task and who was previous owner of the task.

It doesn't look like Lizzie has updated that since 2012 - I haven't tried it on recent versions. But, based on what I remember, it actually cancels the task and creates a new one when you reassign it via the plugin; so you could include cancelled tasks in your report, perhaps.

I do remember that since it essentially cancels and recreates the task, the "clock" on the task is restarted. So, be careful using it if the task needs to be completed within a certain timeframe.

It doesn't look like Lizzie has updated that since 2012 - I haven't tried it on recent versions. But, based on what I remember, it actually cancels the task and creates a new one when you reassign it via the plugin; so you could include cancelled tasks in your report, perhaps.

I do remember that since it essentially cancels and recreates the task, the "clock" on the task is restarted. So, be careful using it if the task needs to be completed within a certain timeframe.