Last year I submitted a manuscript to a journal. The guidelines said that it can be written in British English or in American English, but not mixed. So I chose British English.
Now I must resubmit after revision, and see that they changed the guidelines, which are now:
English spelling should follow the Concise Oxford Dictionary. Authors might also wish to consult Fowler’s Modern English Usage (ed. R.W. Burchfield; Oxford University Press) and Scientific Style and Format (eds Council of Scientific Editors; Cambridge University Press).
Does it mean, that I still can use British English? I don’t have these dictionaries, so I am not sure about it. Wikipedia does not clearly say which flavour of English it is.