RunMn, I stopped running only after I basically could not run because the pain was too severe. I ran with some pain for a couple weeks. Once I was pretty sure what was going on (I'm a medical person, and I did a lot of research) I stopped running and started recumbent exercise bicycle, and some elliptical, alternating between the two (essentially intervals, in the same workout) as tolerated. I did not have any pain with either activity. Once I had my bone scan and diagnosis, and saw the sports med orthopedist, she told me anything that did not cause pain was okay. Neither elliptical or bike caused pain, so I continued with both the entire time (and I think they saved my sanity!) I did do INTENSE workouts, too, up to two hours at a time, a total of 6 miles on the elliptical and 30 on the bike. Heart rate up like running, if not higher.
I did do a bit of walking, at the advice of my physical therapist, (she said weight bearing exercise was important to healing) but typical of a runner, walked too fast, it hurt and I had to stop. I knew it was okay to try a run when I no longer felt twinges when lifting heavy things (like a bag of cat litter, 20 lbs) and that was my best gauge of healing.
so, I think I would say that cycling should not be a problem unless you experience pain, and see what your doc says about elliptical. Up to you how intense you wanted to be but I am hooked on those endorphins and could not bear the thought of regaining the weight I lost a couple years ago. Did my exercise throughout this time period extend my healing timetable? I'll never know but I don't think I'd change anything if I had to do it over other than maybe not doing that walking like I did.
Good luck...