It may have to do with the fact that you are standing out in the open of the stairwell by yourself. Ciira has ducked back into the cooridor to shield herself from the incoming blasterfire...
...which erupts from a dozen blasters at once, setting the desk barricade aflame and blasting up the stairs around you. You notice that the droids become visible each time they pull the triggers of their blasters, but it is something you cannot capitalize upon just yet. You take damage that knocks you up to 76 damage and a Death Check (passed).
Rianna decides to give up a Luck re-roll to catch on to what her senses are telling her. Just as the droids open fire, she backs up onto the balcony where she is just out of range. The droids still blast up the stairwells where her barricades were arranged, setting the desks aflame, but she is clear of damage.
Once you get out of the way, though, the droids stop firing and you cannot tell where they are... until they start marching up the stairs, bumping aside blasted parts of chairs and desks. You have a few moments before they reach the top of the stairs.
"Rianna!" Ciira says. "What are you doing?"
Not from where Ciira is, but yes.
But Ciira seems to have other plans.
"Great, but we can't fight all of them at once," Ciira says. "Master Jeph always told me that in situations like these, one should try to narrow down as many attackers as possible, take advantage of your position when you can. If we let them come into the hallway, we can cut them down one at a time!"
The waiting game commences, then, as Ciira conceals herself in a doorway opposite of you, lightsaber in hand but unlit.
The droids progress up to the balcony, as you can tell from their clanking feet. But after a moment of glaring in that direction, you can tell something else... the concealment is not complete. There is a faint blur in the space where the droids are standing. The light from the now open door is distorted.
They decide to move into the cooridor...