BladeFall of Trarthus with Whisper's of Infinity

Have confirmed as others have that when you get hit and the natural ES Recharge is disabled, BF of Trarthus starts to degen at what appears to be way more ES than last league. If its supposed to be 5% of mana, my natural ES regen would outpace this degen. As of now, it appears to be draining at somewhere in the 5% to 10%. I tested whether it is BF that is the culprit by getting hit in a map and as the degen happened, I disabled BR in my buff bar and my ES immediately regened.

This is preventing me from being able to successfully do maps and I would really like if this bug was looked into. Or if this is not a bug, I'm curious why it was not included in any of the patch notes? Either way, would love if this was fixed!

Thanks,