I´m pretty sure that many players have posted about this already, since Azir shows us an another bug once again~ So, Azir´s soldiers seem to loop their AA animation while targeting nearby enemies like usual, except they don´t deal any damage and continue to do so even if Azir himself is just standing. I got Sand Soldiers´ AA animation stuck into a loop by first casting Q, followed up by one quick AA. When I cancelled Azir´s "finger pointing" -AA by giving a move-command, his soldiers kept on doing their own AA animation until they were commanded to hit something else or until they disappeared. Also, if there is no one in their range, they just keep on hitting towards the same direction as the initial AA.
EDIT: It seems that AA starts to loop when you try to cancell Azir´s AA animation as soon as he orders his soldier to attack. The use of Q is not required.