I recently attended an editiorial panel at a conference where editors of several journals in my field advertised their journals and to this purpose listed, amongst others, the time difference between editorial acceptance and online publication.
While the averages they gave were about one month, I cannot recall any paper of mine or my colleagues in this field for which this took longer than two weeks. We get the proofs within a week, send our corrections within one or two days and the paper is published a few days later. Add two days for the rare case that another round of proofs is required.
I can guess several reasons for this discrepancy myself such as:
- authors not returning the proofs in time
- bad figures that require reworking
- bad English that requires a lot of copy editing
- a strongly skewed distribution of acceptance-to-publication times (but then journals would probably use the median and not the average for this statistics)
However, I am interested in something more substantiated than a guess and thus in any statistics or hands-on experiences from a copy editor or similar as to what usually makes up for the time between acceptance and online publication, which in turn could explain these discrepancies.