yoga after tummy tuck

Hi all!  I had a full tummy tuck 16 days ago and am enjoying an unexpectedly smooth recovery -- although I realize I'm not out of the woods yet.  In spite of all the research I did before surgery, somehow I managed to overlook the part about not doing any serious ab work, such as yoga, for three to six months after surgery (my PS told me six months; docs on the internet generally say three).  I plan to listen to my PS and wait for him to grant me permission to increase my activity.  But now I'm wondering:  How do you know when you're ready?  Even after my PS gives me the green light, how will I know that my MR is really, truly up for some core work?  How do you know for sure when you can do a serious backbend without rupturing all your internal sutures?  Those of you who do yoga, what has your experience been? Many thanks in advance for your advice!