Did they create a groove or repair/reform the peroneal retinaculum that holds the tendon down?
I would be very cautious regarding rushing the recovery from that type of surgery. I have worked with one other athlete who has a peroneal retinaculum repair (he tore his retinaculum and had a subluxing peroneal tendon). We took things very slow as you do not want to stretch or damage the new/repaired tissue, because if you do the tendon will just end up subluxing/shifting again and you will be back to square one.
Listen to you doc regarding it and do not rush it. Meanwhile, continue to strengthen your healthy leg as normal.