Post-ga verification shown that almost (maybe all) artifacts has been built anew - meaning that timestamps differs within each artifact. This means that there might be some problem with PNC.
For example:
https://maven.repository.redhat.com/ga/antlr/antlr/maven-metadata-local.xml has <lastUpdated>20170105084415</lastUpdated>
where the same file from downloaded mrrc has:
<lastUpdated>20200127122413</lastUpdated>

same goes probably for each artifact (over 7500 occurrences).