I believe this is working as intended.

https://security.googleblog.com/2016/10/distrusting-wosign-and-startcom.html
Certificates issued before this date may continue to be trusted, __for a time__, if they comply with the Certificate Transparency in Chrome policy __or are issued to a limited set of domains known to be customers of WoSign and StartCom.__

Due to a number of technical limitations and concerns, __Google Chrome is unable to trust all pre-existing certificates while ensuring our users are sufficiently protected from further misissuance__. As a result of these changes, customers of WoSign and StartCom may find their certificates no longer work in Chrome 56.

__In subsequent Chrome releases, these exceptions will be reduced and ultimately removed, culminating in the full distrust of these CAs. __

Correct, trust in StartCom and WoSign certificates is in the process of being removed. Chrome 58 removes a substantially larger number of these, and Chrome 59 will continue this process, due to the issues noted in that post.

But both valid and invalid certs are based on same issuer. There is no any difference except two weeks shift in valid from date. That's understandable.

The difference is that they're issued for different domains.

All certificates from these issuers will eventually be distrusted. The priority of distrust is that certificates for the largest sites are being distrusted last, in order to allow sufficient time to replace or find alternative certificates.

www.airtime.pro's certificate will be distrusted in a future release.

got it, thanks!