LOL at people saying this might be QC related. Because HT are all about that QC.....
And smart money wouldn't be on an improved sculpt, either.
You can't rule it out, unless you know something we don't Just a possibility along with about 3 others listed. Could be anything really, but I don't think it's the real reason for the delay. It's probably delayed due to the huge amount of figures being made by them, so we just have to sit back and wait longer.