Then the issue probably lies elsewhere.
If printing the elements of the array one by one only leads to 9 elements and checking the nodes in real time says that the array has only 9 elements, then there's probably only 9 elements in the array.
for n in array statement should always allow you to iterate to every element in the array. Also as suggested by @Ertain, looking at the [Remote] scene tree should allow you to view real time what is happening to your array. If you click on the relevant node that holds the array, the [Inspector] tab should give you information regarding the array under the [Members] section. From there you'll see your array and it's number of elements. Clicking that specific array, should expand it to allow you to view the values it contains.
It would help if you could post a snippet of your code. It's hard to guess why there's only 9 elements.
PS: If your array has more than 10 elements, you'll see another entry called "Page",
where Page 0 shows the 0-9 elements, Page 1 shows 10-19 elements, etc...