Face of the Mountain Shield + Tahm Kench Bug

If you play as Tahm Kench and use the Face of the Mountain active near the end of your grey shield's decay time, the shield from Face of the Mountain will end at the same time that your grey health ends instead of the full 4 seconds like it is supposed to. Hope this gets fixed soon as Face of the Mountain is a core item on Kench and it feels like the shield from it is wasted a lot of the time cause it only lasts 1 second instead of the intended 4.

https://www.youtube.com/watch?v=AP_ZWZVFgxw&feature=youtu.be

Here is the link above. Watch Tahm's health bar and you can see near the end of the video that his shield grows for about half a second when I used Face of the Mountain, only for the whole shield to disappear when the grey health wore off when really the Face of the Mountain shield should have still been there.