One interesting thing that Backblaze supports (that I don't think many people use) is that you can actually use any S3 API on any bucket, and any B2 API on the same bucket. Like every other call if you want.

So if you HAPPEN to find something is more clear with the B2 API, it's fine to use those calls on a bucket. If you find something is more clear in the S3 API, it's also fine to use those calls. The bucket won't get confused. :-)