First of all, good news everyone, there’s already a werk – we hope it to be released for 2.1 around next week, no assured date yet though: Fixed removal of persistent acknowledgements 
And about your question. This issue was assigned and the work on it was being done – as I tried to keep you updated on this, you can see that it has been in progress for some time. I cannot comment on processes of the development team but I can say that this bug, or any other report, did not lack attention and was not forgotten in any way.