It is also possible that they have updated other things on 15th Feb.
I have checked OP and the 10 days trading term is there and also on TG. So, in my opinion, it is not a piece of concrete evidence to tag the bounty manager unless other participants confirm the same as cybersofts. If other participants confirm the same then it is a concrete evidence.
Moreover, btcltcdigger haven't responded to the accusation yet, we need to listen what he has to say.
Please correct me if I'm wrong.
As I mentioned above, Vanta Bounty started on January 16, 2019 and to add, it was supposed to end on Feb 17, 2019
Before it ends, the update was announced that the bounty be will be extended up to March 4, 2019 together with new requirement which was the 10 trades. Check the link or the image posted by cybersofts here. Idk when exactly btcltcdigger update the thread, but what's for sure is that it's not on the start date of bounty because VNT was listed on ALLBIT on January 30,2019 as per announcement.
You mentioned about tag, to make it clear, I'm not posting this to make btcltcdigger tagged. I was just sharing the information. Also, btcltcdigger can reply here anytime to make things clear about what happened.