is that code for simultaneous movement of servo motors??
The rotational speed of R/C servos is so slow compared to arduino program execution speed that yes all servos controlled by the servo library can be 'simultaneously controlled'. A position command sent to the servo library is only one instruction is time span, the servo library continuously keeps sending the last position command on a interrupt basis while the sketch continuous on to other statements in the sketch. How long a servo takes to reach the commanded position is of course determined by it's starting position relative to the new commanded position, and a little dependent on the mechanical load attached to the servo.
If a Arduino can turn on and off 125 leds in my 5x5x5 led cube without me seeing any sign of flicker is it controlling all 125 leds simultaneously? No but in reality it appears to be.