I tested the possible variations, here’s what I got
Both combinations are working:
1) With AFC set to textfield and html tags conversion.
2) With AFC set to textfield and carriage return conversion to <br />.
3) AFC set to WYSIWYG Editor in any combination not working.
What works only works with a new blog post set up.
It is not working when the AFC fields simply get updated after the field setting is changed to reflect the the right setting (1&2).
Anything I can do to get 850 entries to work upon editing and updating?