S_Retime OFX in Flame

So I’ve been experimenting with S_Retime plugin in Sapphire in Autodesk Flame and the retiming works however it seems like if I retime a clip to slow it down, the slow down is not reflected in the timeline in terms of increasing the handle length.

For example, if I have a clip and slow it down to half it’s normal speed then exit the S_Retime controls, I still have zero handles in the clip on the timeline. If I used Flame’s native retiming effect, I am able to see the change in handles as I slow down or speed up the clip.

Perhaps, I am doing something wrong or is this a limitation to OpenFX?

Thank you!