To further clarify – it is the “Featured Sponsor widget whose content continues to disappear or reappear in partiality only. (There should be 9 ad units showing).
I have inquired as well with the ad software (passionfruit ads) that provides to code etc. but have not received a reply. On the PR page, the ad shop often spontaneously disappears as well as the html code, and I have to constantly re-insert the ad shop script.