I had questions about DS a year ago at 5 as he was flipping letters and had a great deal of difficulty writing We heard the same things - too young, too gifted to test because he actually reads quite well. But I am dyslexic. After all the testing with an OT, we determined his writing is primarily an OT issue. However, we did get him vision tested and he has difficulty tracking things across but not down lists. We are going to a more sophisticated test of his perceptual vision to determine what he sees. We went to a teaching hospital/school, they were very helpful. I would recommend those tests to rule out, rather than rule in dyslexia.
Also he is no longer flipping numbers and letters - so that might have indeed been appropriately developmental - but his words are still huge and he has trouble with spacing between words and internally. I have to have a conversation with someone because his supply list calls for wide ruled notebooks and he can't write on them!
DeHe