You seem to be citing a reply from me so allow me to clarify: getting dupe shards on your 3 stars is not a bug, but rather— there was a bug which caused much faster progression and acquisition of 3 star champs. Players hit duplicates in a matter of days, when designers had balanced it out as taking weeks. Designers expected to use that runway of several weeks to iterate on some solutions for dupes.
Future plans of how the economics of shards would be balanced are a bit out of whack now— so we are rapidly working on a new solution for dupes.
This may require new text (localization), new iconography, backend logic, and some other light frontend pizazz. This means it's not a fix a lone designer or engineer can quickly turn around in a single patch, but instead it's a multi-discipline, multi-week effort (more akin to a small new feature, or QoL update).
I understand the frustration— I myself am sitting on two 3 stars with more than 40 dupe shards. Rest assured that we have folks diligently working on addressing the issue. Apologies if my communications elsewhere gave the impression that we were dealing with a simple bug we could squash out easily, and not the more systemic snafu we've got to work our way out of!