Unfortunately no, you will not be able to do future workouts. Each workout that you do is based on the feedback from the previous workouts you have done! So for this reason, your workout schedule is curated perfectly for where you need to be at that very moment!
If you would like to do more workouts you can always add workouts to your schedule using the Simple Scheduler at the top of your My Workouts page! However, you cannot do workouts early, as each day's workout unlocks on or after that day of the week.
However, you can any access a previous day's workout and repeat them as many times as you'd like throughout the week!