FA - rise attack in bm1

I found some info about rising attack at offical cabal website.
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"Bug Fixes / Corrections
3. Corrected a bug that allowed Force Archer’s attacks to rise while using “Multi Shooter” skill consecutively in certain circumstances"

Do You know what triggers this bug?

Nope,i just know that this has happened to me a few times whilst owning pubs in 139 NW.. Been doing 7k crits on guardians with BM1 usually, went up to 12k sometimes using BM1. Never understood why.

yeah even me that bugs happens and it ROCKS!