Jarvan IV Frozen Heart Bug

Me and a friend were testing the new Black Cleaver and wanted to test how much shred it did with Frozen Heart. I wanted to test it with an item that gave max armor to see the effect. We tested it various stages. One with purely Black Cleaver and the other with Frozen Heart. When Jarvan IV AA's a target, the BC proc went through without a problem even with Frozen Heart. However, when Jarvan uses his kit with or without the combination, it resets the armor halfway through the BC proc.

Unless something is missing, Rito please please please look into this.