a0691627_xporting_and_Importing_Content__import_Behavior
[Case] Region type mismatch Note: Available region types are item, portlet, tab, and subpage. [Source] Region_X – Type A [Target] Region_X – Type B [import Behavior] 
When there is a region type mismatch, all the items and portlets under that region (including user personalizations) are removed from the target and re-created with the items from the source region.
Exporting and Importing Content