Affected Sites: SomeHosted Sites
We have noticed that some sites are receiving 403 errors since the 5.1.13 update. We are currently investigating the root cause so that we can fix them. Sorry for the inconvenience!
2004UTC - We have determined the cause of the issue and have tagged up a new release to address the root cause. This update will be going out to all sites within the next 2 hours.
2221UTC - All sites have received the fix for this issue.