Good point. Right now we have to rely on Joomla!'s update feeds to decide which version of Joomla! to update to. Normally, Joomla! should only recommend updates to the current version branch (e.g. 3.3.3 for all 3.3.x sites). However, we cannot guarantee this will be true. It is possible that, say, 3.4.x will be proposed for all 3.3.x sites if a major vulnerability is found in Joomla! 3.3.x. This may or may not happen and it may or may not result in your site having a problem due to incompatibilities with third party software.
Since this is outside our control we recommend backing up your site frequently (at least once a day). This way –even in the very unlikely case of inadvertently upgrading to a newer, incompatible branch– you will have a way to roll back.
Nicholas K. Dionysopoulos
Lead Developer and Director
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