I attach a picture where I have a time signature of 2/4. As you see in the first notes there are the equivalent of 1/4 group of notes then a bar line and then the normal bars with 2/4 begin. Why are the equivalent of 1/4 notes at first besides the 2/4 text and they are not marked? What is the name of this? For me should be marked first 1/4 with text and then the next bar 2/4. Then what is this?
In Sibelius how do you enter this? Because if I enter 2/4 it will want to enter the equivalent of 2 quarter notes, not 1/4 if it is note described previously.