SoftLayer support asked me to ask this question here at stack overflow, so I am asking here and hopefully someone internal can answer...
According to January 11, 2016 note from here: https://softlayer.github.io/release_notes/
SoftLayer_Product_Package::getLocations() is deprecated. When will it be disabled? January 18th?
There is not currently a date when SoftLayer_Product_Package::getLocations method will be disabled. So as the release notes, we recommend to use SoftLayer_Product_Package::getRegions, since it contains the correct data.