The ops female is 21 months old, by time it would lay would be well over 2 years old. Not sure where you got 1 year old from.
The 1500g 3 year rule is fine and dandy for you to follow but its not a proven fact females must be this or they dont breed. Also not good to push it on others, experience prevails what one individual is comfortable with doing with THEIR snakes.
And breeding small females or young does not cause aborted Ova. This occurrence is very very rare. And the exact cause is unknown as to why females do so, cause some females have done it whos never been bred.
Ive stated this hundreds of times. There's a 6 years old female in my collection, I raised from day one. Shes barely 1400g been that size entire life, and has dropped consistently 5-8 eggs every year since she was 1.5 years old. Females being larger dont ensure better results on clutch size.