Task date changes when marked as complete

Copper Contributor

I help support a portfolio of projects using Project for the Web. Only one project has noticed/reported this bug to me  and I can't replicate this issue, so wondering what might be going on. 
When the user selects the circle to indicate it's been completed the task date changes to another date (often a date in the future). 

I checked and there are no dependencies attached to the task.

It is only happening on a few tasks within the one project that I'm aware off. 

What can I do to stop this from happening or is there a bug in the backend?

1 Reply

I've not seen this before @Kletts , if the user changes the % complete column on the grid view to set 100% for the task do they see the same thing? What about if they use the Board By Progress view and drag the task to Completed?