The photo was taken 7 Jan 2016.
On Tuesday 12 Jan 2016 20:07:41 GMT, she posted a new thread on the purpleport forum for portfolio critique "First Topless", stating
"taken by the amazing PhotoFervor, what does everyone think?

".
People replying saying that it was classy and that she was beautiful.
And then photographer replied (Tue, 12 Jan 2016 20:45:36 GMT), stating "Thank you everyone on behalf of both us great comments

".
At that time her portfolio stated that she was 18. (And 5'8'', 32C-28-34, dress size 8, shoe size 6, and weighing 9st 7lbs...)
So, her defense is that she lied about her age? And so she knowingly spread an underage photo of herself? Someone should probably report her.
Now, I don't currently have access to her purpleport portfolio, but her profile on modelmayhem states that she's 23, so she would have been 19 in April in 2016.
So, unless there's actual proof presented that she lied about her age, no one needs to be worried.