Q: What should I do if I mistakenly chose 'Open Access' when submitting my manuscript?
This was my first time submitting a manuscript, and I mistakenly chose ‘Agree’ on the Open Access (OA) agreement. I later found I needed to pay 3,200 USD (or more, if the manuscript is longer than six pages). Do I need to write to the journal? If so, what should be included? Or I can just wait, and change my option on the OA agreement when the manuscript is accepted?
It seems you have submitted to a hybrid journal, one that publishes both subscription-based and OA articles. As you said it’s your first time submitting a manuscript, the error is understandable. However, it would be better if you write to the journal now rather than later. This is for several reasons.
As you have not mentioned that the status has changed, it seems the journal has not looked at your manuscript yet. So, they haven’t yet expended any effort on it. If you inform them after they decide to send your article for a peer review and the article is reviewed, they would have put a lot of effort without you offering to pay for it (which is what you will be doing if you do not inform them now). So, with an aim to be both earnest and ethical (especially as this is your very first submission), it would be best to inform them now.
You could write to the editor explaining that it is a genuine mistake. The editor may ask you to change the option or submit again; go with the way they guide you on this. All the best for your first manuscript!
As you seem relatively new to the submission process, you may also find the following resources helpful: