To edit your Paper's Editor's Note, access your Paper Settings Dashboard, by clicking the settings/cog icon at the top right of your paper's front page, while logged-in to your publisher account.
Then choose Global settings.
There, you will find the field where you can alter your Editor's Note.
Maximum character length An editor's note has a limit of approximately 10,000 characters. The number is approximate because the field is converted from HTML to plain text; formatting (bold, italicized, etc) may take up some characters.
A note... on Editor's notes
Some publishers write an Editor's note and their intention is for the message to remain throughout multiple editions.
For others, especially those publishers using Manual Publishing, the Editor's note is used as a place to record a message for a particular edition. For this group of careful curators, it's important for the message in the Editor's note to match the exact edition they curated.
If you're one of our publishers who change their message regularly to match a particular edition, please keep the following in mind:
Editor's notes should be added soon after an edition is created/published (for both draft and automatic editions). The note saved for the edition shown in the archives will be the last note present at the time the edition is archived.
When is an edition archived?
Generally, an edition is archived whenever a new edition is created. But if the edition was created using Manual Publishing, the published draft is auto-archived after 21 days, even if a new edition is not created.
Things get trickier if you are switching back and forth from/to Manual Publishing to/from Auto Publishing! Doing so may shorten the time you have to edit your paper before the edition is archived and is not recommended.