Note that the $0.04 price is likely "cold storage" via glacier, which is cheap for write-only storage ($0.01/GB/month) but it's much more expensive than S3 for retrieval ($50/million requests to S3's $1) and there's ~4h round-trip to get data back according to Colin's old analysis of Glacier for Tarsnap: http://www.daemonology.net/blog/2012-09-04-why-tarsnap-doesn.... I'm guessing the data in cold-storage will not be interactible-with or visible in the interface.

Note that the second-to-last paragraph of Colin notes the possibility of tarnsap "glacializing" a complete machine dropping storage costs to 3~5c/GB/month, but it not be readable or deletable save by "deglazializing" the machine (15~20c/GB) to move the data to S3 for retrieval or deletion.