Let me share the progress for this week.
I have successfully finished my task #1 that required me to add write barriers to the PMC methods (https://github.com/parrot/parrot/issues/1069).
For this task, I had finished most of the work last week itself (http://www.parrot.org/zyroz3).
This week I mostly verified all the WB annotations for one last time and it did help me to fix some bugs and incorrect WBs. All this work is now part of our latest release for Parrot 6.5.0 and we have achieved a speed improvement of around 2.5% - 5% through this task!