This has become a very common question here in Los Angeles. I think it is because California has some of the most progressive reproductive law in the country.
The bottom line is that your breasts need to return to their normal size, and that amount of time will vary.
Some donor's breasts get huge, others don't. It depends on your dose of drugs, how long you were on them, whether you had to sync cycles or did a frozen retrieval, and how your body responded.
I just tell patients to wait and be sure their breasts are back to baseline. But this is something for you to speak with your own plastic surgeon about.
And you are to be congratulated for helping a family trying to start a family. You did a great deed.