The original design for PI Tagname is such that under the hood, we do not differentiate based on capitalization. As such, if you were using something like PI SMT to rename a tag (under Point Builder), since we do not differentiate based on capitalization, if you were to change capitalization, we evaluate that as being the same Tagname thus you're presented with an error. Due to legacy backwards compatibility, we have no plans to differentiate Tagname based on capitalization.
