I just would like to understand how to deal with this situation!

Basically our manager had clear schedule on who is working and not working over the Christmas. I took my vacation accordingly as I was a prime person for December month-end activities which is regular part of our job on monthly basis.

I completed what was necessary on 23rd December before leaving on vacation for 3 days and so does my co-worker who was off until next 4 days.

I was supposed to finish month-end activities on 27th December, upon my return, but when I logged in I found my co-worked worked on 24th, 25th, 26th of December and finish all the work pretty much which was on my plate to finish on 27th.

Now, I cam early morning on 27th still got online on time and when I opened up system I found all these!

I really don't know how to react to this! As I feel upset as well as have little bit worried about co-worker as well!

The reason why I feel upset is because, we decided who goanna work on which tasks, I was not late on any of those, there were absolutely 0 requirements to work on Christmas and day after. I planned my work accordingly so that I can stay on the course to finish month-end activities and now I got up on 27th and see everything was done over the holiday. I was thinking if he would have said this before I could have planned my vacation accordingly but when work was distributed he didn't raise this issue at all.

And, I am worried about her as she is supposed to rest over holidays but still working and may be he feels some sort of competitions or something between both us.

Could you please help me how to tackle this co-worker as this is not the first time, he has done this ...working over holidays / weekends and take up my work?

Thanks in advance!

HPP