As i understand it nothing has been deleted, just rearranged so that posts that are more 'personal' are now more likely to be in a "non-public" section.
Also, posts which are "extra-curricular".
[Edit note, 5:37pm ET: For clarity, I should say "advanced material" which goes above and beyond the expected comprehension of Epicurean philosophy, such as interior decorating or making pencil sketches of Epicurus.]