Q: How long will it take for the journal to reach a decision on my revised submission?
I submitted a revised version of my paper to a scientific journal and it took up to one month for the status to change to “required reviews completed.” Why does it take so long? If the reviews are done, the editor should inform the author. But I think I'm just a little anxious to know the final decision. This is a very important paper.
When a journal editor receives a revised manuscript from the author, he/she can either choose to review the manuscript himself/herself or send it for another round of review. While usually the editor sends a revised manuscript to the same set of reviewers who had reviewed it earlier, he/she can also send it to a new set of reviewers.
In your case, I think completing the second round of review in a month’s time is reasonable. Since required reviews are completed now, the editor will look at the review report as well as your manuscript and see if the revisions are satisfactory. There is also a possibility that the editor might not be satisfied with the reviews and would want to seek an additional review. If so, you may see the status changing to "under review" once again.
I can understand your anxiety about the journal’s decision. However, you have to wait for the next status change to get more clarity. Once the decision is made, you will hear from the journal soon.