Editor asked me why to change the corresponding author

Question

I have one accepted manuscript waiting to be published. During the proof, I changed the corresponding author from me to my postdoc adivsor. Editor now asked why I made such a change.

What happened was that when I submitted my manuscript, I am the corresponding author by default. I failed to find any option to change it. So I planed to change it later on.

What shall I respond in order not to be rejected during this stage?

I am major in the theoretical relativity physics.

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Update:

After nearly one week, my request finally is approved. I do not even have to fill out a form.

Answer 1

Just say what you said here: you intended the corresponding author to be one person, but accidentally set it to the other. That's a fairly unexceptional reason to change and I wouldn't expect it to raise any major issues.

Answer 2

Give them the honest reason. Modifying the list of authors is suspicious because incidents where authorship was purchased have happened before. You're only changing the corresponding author, but from the editor's point of view, better safe than sorry.

Since you weren't acting unethically, you shouldn't have to fear a rejection, either.

Answer 3

I suspect that there is no chance that you will then be rejected. Just say what happened and why. I'm pretty sure the editor want to know why rather than be looking for a reason to reject. If you are at the current stage they already have a lot of effort in your paper that they wouldn't want to waste. They would much rather publish such papers than not.

But you may have caused a minor difficulty in their record keeping.

An outside chance is that they are wondering if they need to improve their system or the information they give people.

Another wild guess is that they want a bit of assurance that all authors are on board with the change and that it isn't a case of closing someone out at the last minute.