I'm on LTD since Feb 2020 (almost 4 years) due to CPTSD, major depression, anxiety, panic disorder and recently mild cognitive impairment. I used to be an Executive in a Sales role. My income was a combination of base salary and commission. I had a very high income.
I would like to know if under the concept of "any occupation", the insurance would need to consider my commission as commensurate as well, or only my base salary?
Would the commensurate amount be adjusted to the current year?
If my Doctor says I'm able to go back to work does he needs to consider : another occupation must have commensurate income and must be a position claimant has the training and experience for?

That is a very interesting question. I can see the insurer arguing that commensurate income would be based only on the "insured" amount upon which your LTD payments are based on. If your monthly LTD payments are calculated only on the basis of your base salary then I can see an insurer taking the position that the commensurate income is calculated on that amount, rather than your base income plus commission. To counter that argument we would need to examine the wording in your LTD policy as that ultimately determines your rights and the insurer's payment obligations. Conversely, if your LTD amount is based on your base plus commission then the commensurate amount would be based on that combined sum. In terms of any adjustment, that factors in if you have (in your LTD policy) what we refer to as a "COLA" provision (Cost of Living Adjustment). If you do then your LTD payments should be adjusted, and arguably the commensurate income considerations would be based on that. However, if you don't have a COLA provision in your policy, there will likely not be an adjustment.