This is my personal opinion from my experience in the matter.

In regard to MCRS and Veteran Affairs entitlements, dual eligibility does not mean you should claim under both systems, instead; you should be recognised under both systems in case one doesn't cover an aspect of your situation, you may be able to claim the same / similar entitlements under the other.

Too often, people get confused from seeing what I've seen thus far, and think that dual eligibility means claim monies under both systems, if you can, and get more. This is wrong and not the actual facts at all. For those that have active service in a recognised zone under Veterans Affairs, you are better off to simply claim under Veterans Affairs, and not split your claim. Why? Well, because one does affect the other in that case, so all you are doing is actually placing yourself in a possible worse situation financially, with the same sum of money coming from different sources. Claiming under both does not give you more money, it simply splits the total sum and you receive it from two agencies, instead of one.

What you need to do, if applicable to your case, is simply be recognised by both, ie. place in your paperwork too both for recognition of illness caused from military service. You are better off, in my opinion, to simply claim under Veterans Affairs, through a delegate, and simply be recognised by MCRS. If Veterans Affairs fails to provide appropriate support, you then take up the matter with MCRS for financial backing, until such time as Veterans Affairs matters are sorted out.

You may also want to look at the lump sum payment thread for more information.