Sorry--Yet another spay question (Rescue Dog)

[ScottieDog]

I have been approved to adopt an approximately 2 year old rescue. She was spayed when she was taken into rescue. Are there any health concerns I should worry about since she was not spayed before her first heat? I was told that she never had any puppies. My other rescue was spayed at 6 months and I was told that an early spay would help cut down on mammary tumors. I will of course discuss this with my vet when I take her in for her first well-doggie checkup when she comes home.

I am not trying to start a debate about spaying, just ask a question I have never faced before. Thanks.