There have been a bunch of other, similar, threads on the forums lately.
This one might help you with getting ready for your early morning workouts:
This one is more focused on motivation and the mental aspects:
That’s all the preventative care advice you should need and how to reduce chances of actually missing the workout.
Once you’ve missed them you need to assess why you missed it. If you are actually over-fatigued and need the physical break it is fine to replace with a lower intensity workout or do nothing at all - you have to listen to your body. That said - it is better to try and fail at a workout than to let your brain tell you that you can’t do it. Often the hardest interval is the one getting onto the bike and finishing the warm-up.
You have to learn the difference between the (admittedly heavy) fatigue you will feel from a SSB plan and your body telling you to snooze the alarm because it’s easier to just take the day off. This is a highly individual thing, but for most relatively new cyclists you are more likely to undertrain yourself than overtrain yourself