RE: When I went into WordPress this morning and looked at managing entries all three ‘V’s were visible. What would have changed from yesterday?
A plugin update, a settings change and more could change the memory being utilized by WP. So, if the memory usage is right near the edge of the limit, yes, it is possible to experience the issue one time and not another. So, at this point, my recommendation is still increasing the memory allocated to WP. Let me know how it goes.