[Tactician] "Mortar Grenade" + "Flash Grenade" Interaction

Is this intentional?

Particularly at 0:04 and 0:08, after laying Mortar Grenades, my character suddenly looks at a particular monster, rendering me not being able to cast Flash Grenades. At 0:08, I was spamming the Flash Grenade (Q button), only having it triggered at 0:10.

That's 2 seconds of my character just looking at a particular monster. It can be cancelled by casting another Mortar Grenade but there were moments when I was able to cancel it, only for my character to look at a different monster.

Casting Explosive Grenades (not in my skill slot during the taking of this video) could cancel it as well, but it's just not the solution (I'm not running with Explosive Grenades anymore).

https://streamable.com/vrrxif

Edit:
New link below coz the one above expired:
https://streamable.com/vdvxiw