Suddenly, after adding and editing a field to ACF 4.3.9 Flexible Content one of the fields gone missing.
All pages containing this particular field is completly corrupt, much of the content is missing. I can see that the information is still in the database.
The definition is quite complex and big, I see that ACF seems to be saving this as a serialized PHP/JSON(?) array in wp_options. The site has a lot of traffic and it could be possible that something misfired during the save (had the same issue 10 months ago when I updated the definitions)? Or can this be a bug. The serialized array looks correct but is in fact missing the field.
Is there any way to prevent this? I understand I can be hard to reproduce this, but some sort of backup or ability to step back would be great. I tried the import/export feature in WordPress with no luck.