According to the update, Marksmanship aghs arrows got fixed to be avoidable. But Strafe still can't avoid them.

Strafe was also unable to avoid Bedlam projectiles, but it now can, so it looks like the fix was applied to Bedlam only, instead of both.

Note: This is a specific bug affecting Strafe only. Every other disjoint ability can disjoint the splinter arrows normally. Only Strafe can't.

This is the old behavior, pre-spring cleaning 2018

And this is the current behavior