Why did 'X' change in my account all of the sudden?

When new updates to DTM are released, changes don’t always affect a client’s property until their next publish. So, if you noticed something unexpected in your account right after publishing a change, check the release notes to see the time frame for any updates to DTM and compare to the your publish history to see if this was your first publish since the last release. If it was your first publish since a release, check what changes to DTM may have affected your property.

See release notes here - https://microsite.omniture.com/t2/help/en_US/dtm/#Whats_New_in_Dynamic_Tag_Management