If you have 35 years residency in Australia and apply for portability at 67 y/o when you apply you will already have done your 2 years for portability as part of your 35 years of residency. It is 2 years before or after getting the AAP. That is why most long-term residence people get portability straight away.
That is often the case with having the AAP, that is because it is under the tax-free threshold for seniors ($35,000 threshold you pay no tax for anyone over 67 y/o). Some people have to pay tax if their income is over the tax-free threshold in Australia if that includes the Aged Pension..
Yes, I believe there are different rules for returned servicemen. Even if you are not injured you can get the Australian Aged Pension at 60 y/o. Good luck.
OH ...on the Australian Aged Pension Aussies, can do quite well in Thailand. I know Aussie men who live with a Thai lady and a few kids all quite well and happy. Even modest drinkers and fun lovers.. Plenty of them.