That Anavex actually does not know and therefore IR does not know, makes the funny part that some on this mb claim to know that Anavex knows, if you know what I mean.
When I spoke to IR, he said "'around YE 2021' is our best estimate." Since this was just a couple weeks ago, it's likely a good estimate.
And estimates can be wrong or 'missed'. The CRO can encounter difficulties or delays. The sponsor can have questions that need clarification or further analysis.