Hi David,
You can use the most recent AltaVault 4.3.1 release, which supports the new Glacier retrieval methods. When you have Glacier as your cloud target, AltaVault will by default use 'standard' as the method to retrieve data when a prepopulation operation is requested. You can however change the method used when issuing the prepopulation job by selecting 'bulk' or 'expedited' in the options. The operation will then use that method to draw data back from Amazon. Refer to the AltaVault documentation (administration guide) for details.
Regards,
Christopher