as no answer or solution was added from developer, we deactivated plugin from all websites (total 3) and magically all recent problems dissapeared…
but main problem, dear plugin developer, is that at least our websites´s servers are NOT running Low Memory, so maybe is a bug from your plugin update. By the way your´s is a great plugin, maybe first critic was not very accurate, but please review if your update was something wrong, because our server is not low on memory but we also get the message. Thkns buddy!