Ankle stiff and stuck in a flexed 90 degree position post cast, how to start ROM exercises?

I’m 6 weeks post op after a Weber C break w/dislocation. Yesterday I got my cast off, and was cleared to start PWB and PT. I only need to wear the boot when up and about. I’m waiting to hear from PT, and in the mean time my surgeon said to start doing ankle circles and toe curls.

I’m sure this is normal, but it feels so weird to have my ankle basically be locked into 90 degrees and unable to relax. I’m able to wiggle my toes, but it’s super challenging to do any kind of plantar or dorsiflexion.

I’m basically wondering how long this stiffness lasted for others, and how I can attempt to start rom.

Thank you!!