Midfoot fusion and healing time

Hello,

I have had TMT joints 1-3 fused previously. With those fusions good bone growth was seen by 6 weeks post op. On October 16th I had TMT joints 4 and 5 fused and an inter-cuneiform fusion done along with a tendon repair and transfer. At my 8 week post op appointment my surgeon said the inter-cuneiform fusions looks good, but the 4th and 5th fusion didn't show visible bone growth. I of course am going in to have another X-Ray next week to see where it's at, but I was just wondering what the normal timeline is to see bone growth on an x-ray post fusion surgery.

Thank you
Cassidy