I never came across a training program to complete a 230mile expedition. I will try to give you some ideas of how to prepare for the punishing 230miles.
First of all you have to run/walk, a lot on uneven terrain for many hours. The trail is pathless with lots of boggy sections and river crossings. Make sure you are comfortable running in wet feet. Practice that, it will toughen up your feet and possibly prevent blisters from appearing.
Strength training for your upper and lower body is essential. The bogs and wet grass will drain a lot of energy, slow you down. The same goes for the heavy pack on your back.
I have a great strength routine that uses only your body weight. Strengthening your upper and lower body in just 20min, 3 times a week.
Use your backpack and kit as much as possible to get used to it. Fill it up with essentials that you will take on your expedition.
Your shoulders will hurt from the heavy bag but you will get used to it after a while. Don’t get discouraged, it will hurt, but pain is temporary. You will get strong and ready to tackle the trail.
Do not exceed 10% of your body weight in you pack unless you really have to. I made the mistake of having 25% of my body weight on me, extra. My Achilles tendon was very sore after I slipped with all that extra weight.. Thankfully i managed to recover in few days still training strong. Next time I could be not so lucky!
Exercise eating food even when you don’t want to. You have to eat. Practice food you will have with you. Make sure you have variety of food to eat.
Study the map, a lot! Watch videos on YouTube to get familiar with the terrain. It will all come together.
Plan your stops. Check how far you have to villages to resupply.
Locate the bothies.
Practice running in the dark.
Check the forecast. And check again. Rain can cause serious disruption to your adventure. The river crossings are very dangerous in full flow.
Of you are planning to move at night make sure you have sufficient head torches and spare batteries
Do not litter.
Back to training.
The trail is 230 miles long with around 40 000 ft of climbing. You seriously need to put that climbing in your training. Do the distance, do the elevation. Do not worry about the speed. You will get there in your own time.
This is the advice I have so far! If I will come up with some more wisdom I will definitely share it here.