For sure, getting out on some longer rides can definitely be good preparation!
A good (and simple) starting point would be to add in those longer rides when you have the time available to do so. Upon completion of those longer rides, Adaptive Training will step in and make changes to your plan if any are needed.
Another way to do so would be to use TrainNow and Workout Alternates. Workout Alternates, in particular, will allow you to find substitute workouts that are longer/shorter than what you have on your TR Calendar on a given day, so it can be an awesome tool to use if you’re looking to switch up a single workout’s duration.
You could also try adjusting your plan’s volume (instructions here). You may, however, see training stress warnings appear from Red Light Green Light. If you feel like you can handle the additional volume, you can proceed – but do so with caution and be mindful of how you feel moving through your plan. If you feel too much stress/fatigue building up, don’t be afraid to back things down again.
Other athletes here on the forum have set volume “ceilings” in that part of the Plan Builder setup, meaning that Adaptive Training will start them out with shorter workouts based on their current Progression Levels, but, as they train, AT has the “headroom” to slot in longer duration workouts as PLs in each zone increase.
Finally, you can also adjust Adaptive Training’s Training Approach, which will determine how “easily” you get yellow/red days on your TR Calendar. A more “Conservative” approach will cause yellow/red days to trigger at a lower threshold than a more “Aggressive” approach, which would conversely allow you to take on more training stress without sounding the RLGL alarms.
Again, though, make sure to check in with how you feel during your training sessions and really prioritize your recovery if you choose to bump your volume up. If you start to feel too fatigued, some extra rest/recovery can be a real season-saver!
Hope that info is useful – let me know if you have any other questions on that!