Hi
The AMH test is supposed to indicate the number of eggs you have left. The problem with the test is that it does not tell you the quality of the eggs.
So you can have a good high number of eggs and they all be genetically such that they will not produce a pregnancy, or the opposite extreme of having a very low number, that would seem hopeless, but it only takes one good egg.
This makes the AMH test fairly poor indicator of future fertility.
Having said that, I would be concerned delaying ttc til after forty, as it is not only the number of eggs that reduces but the quality too,
My personal experience was of conceiving easily in my late thirties, but turning 40 has produced the heartache of recurrent miscarriage due to age. I would not advise putting off ttc any longer than needed. Each year makes a difference.
Obviously if you can afford and are happy to try donor egg IVF, then that gives you more time if needed.
If you definitely have to delay, then while you are in the states still you could look at checking out other factors that could affect fertility, eg scanning uterus, checking progesterone levels regarding ovulation etc.
I hope you don't mind my suggestions.