Her latest measuring video on her onlyfans is insane
Measurements
Bust: 142 cm / 56 in
Underbust: 82 cm / 32 in
Waist: 76 cm / 29 in
Booty: 127cm / 50 in
Left breast: 4.7 kg / 10.3 lb
Right breast: 4.9 kg / 10.8 lb
Depending on her leaning bust measurement and her lying bust measurement (plus a few other variables), we’re looking at a 32Q/QQ (which doesn’t really exist in real world fits).
The only bra brand I can think of who would make an accurately fitting bra in this size is Optifit.
Most amazing fact is that she is all natural. 
Yes - and it’s a curious thing. Pregnancy, hormones, weight gain, natural growth - all come into play here.
As I said in a previous comment, having seen some naked pics, it’s noticeable that her boobs have a significant teardrop ‘droop’ to them (trust me, this is common - most women with big boobs get it. I certainly have it), which tells me is mostly weight gain. Also, she’s really slight in the frame (and not especially tall), so even minor growth will appear so much bigger.
Personally, I think she’s just so pretty - and what a shape she has. I just hope it’s manageable - and she can find bras that (mostly) fit and give her support and comfort. Life is hard having boobs that big - both physically, and psychologically.