Is It Right To Take Dulcolax At The End To Have A Colonoscopy?

Hi, I am having a colonoscopy tomorrow and am prepping tonight. The instructions say to take Dulcolax before the drinking a Miralax/Glycolax mixture. It also says after the drinking all of the liquid (64 ounces), it says to take the Dulcolax one hour after taking the last of the Miralax mixture. I just want to make sure that taking the Dulcolax at the end of the process is the right thing to do.Thank you