It sounds like she is doing fantastic!
Nighttime potty training is different than daytime potty training. For nighttime dryness to occur, the body must first develop a hormone that signals the kidneys to slow urine production when the body is asleep.
It sounds like your dd has developed or is developing that hormone. I'd wait a bit longer to see if this is really a consistent pattern.
Second, your child has to learn to awaken to the sensations of a full bladder in order to be able to get to the toilet during the night if needed. Some children just naturally develop this ability, but some children need to be trained by limiting fluids before bed, taking them to the toilet once during the night, etc. You may need to consider transitioning your dd to a toddler bed in case she needs to get up during the night to toilet.
Your dd sounds like an advanced little gal!