This did not occur to me. Is it acceptable to upload to and rename a series pool created by someone else?
It depends. If it's part of the series, then uploading into it is fine (with the usual discretion* per paywalled vs. non-paywalled content). If the series pool title is not accurate (or no longer accurate, like a sample pool becoming a full one), then renaming it is also fine.
(*Leaving it up to the discretion of the user doing the upload.)
Otherwise (e.g. grouping multiple series into one, changing the translated title to an equivalent one which might or might not sound better), it's best to propose changes in the comments (first page of the pool) or the forums, to avoid potential friction.
