The test is reliable, more so than your meter. Well done on your great improvement! It is real! Few things to remember:-
The A1c is looking at what happens over 24hours a day for a few months. Your tests are taken probably 2 hours after eating when levels are still elevated; they'll be lower the rest of the time
Fasting levels always seem to be the last to come down, and the dawn phenomenon gives us falsely high readings; we are lower than our fasting BG during the night frequently.
The meters we use simply aren't reliable, they are within about 15% accurate IF we do the test properly.
So sit back and enjoy your result, and continue to work on getting even lower