A guide to identifying the differences between a male or female Guppy fish. How early on can you distinguish them? What are the appearance differences?
If they are both female, then one of them was pregnant when you got them. Guppies can hold sperm for up to 10 months, and produce offspring every month until they run out.
She's a tuxedo magenta female guppy. This strain is also called flamenco dancer, HB magenta, Velvet tuxedo magenta, tuxedo pink and HB pink.
So, if the other one has dropped fry, she must have used stored sperm packets. Females of ovoviviparous livebearers such as guppies can store sperm packets in the folds of the fallopian tube for over a year even.