Trending @Infosys; Review compensation

I would like to seek clarification regarding calculation of my promotion compensation. I received a compensation Hike on February 25 which was based on my original joining compensation. However I was promoted on April 17 and I noticed that the promotion compensation is also calculated based on my original joining compensation, rather than the revised compensation post Hike.

Is the expected as I received in the same quarter? I also have two condensation letters.