Can these measures of intervention for dyslexia be taken at any age or is it best to start early?

Yes, they can. There is no limit to the age when disorientation can be corrected, so that dyslexia is just a talent, without the associated struggle. Since a new point of perception allows the elimination of the symptoms of misaligned balance and motion, it stops the disorientation and gives the student great ability to focus.

However, when a child is very young, an intervention is there to prevent future issues, rather than correct them. On the other hand, I have had people in their sixties and seventies do amazing programs and completely change their lives. It all depends on the level of motivation—and often adults display a high level of responsibility and motivation. They have struggled long enough and are ready to take change seriously. I personally find that adding another modality, like EFT or the Healing Code (as also discussed in this book) to an adult programme counteracts negative past conditioning and accelerates a positive outcome.