editing panels

Text blocks on Panel pages and content in slideshows on Panel pages don't always update right away when edited or added -- the same way as, say, edits to instances of simple content types.

Flushing caches will usually force the updates through so anonymous viewers can see the same content as admin.

Is the delay purely dependent on the caching rules in place on an individual site or is there something standard about how soon updates -- to nodequeue content, for instance -- become published?

Can flushing caches this way be a bad thing, if your site is not high volume?

Hi

Please be gentle, only just started using Drupal over the last week.

I have offered to redesign a Drupal install for a friend of mine, after the person who originally installed and built disappeared without trace.
I have designed many cms/blogs/ecommerce over the last ten years, using Xoops, WordPress, Magento etc, but never with Drupal.
I have setup a dev site with a copy of the site and database. I am using Drupal 6.15, I also have CTools 6.12 and Panels 6.32.