I understand that I can only save Blob's in hot or cold tier. Later on I can switch the tier to Archive. Does that mean I pay for the write operation twice. Once to write to Hot/Cold, then again to archive (while switching the tier back to archive)?
[Note: As we migrate from MSDN, this question has been posted by an Azure Cloud Engineer as a frequently asked question.]
Only the hot and cool access tiers can be set at the account level.
When a blob is moved to a cooler tier (hot->cool, hot->archive, or cool->archive), the operation is billed as a write operation to the destination tier, where the write operation (per 10,000) and data write (per GB) charges of the destination tier apply.