Live blend interrupted on scene load

I have two scenes, Scene A and Scene B, each with some virtual cameras.

The game starts with Scene A loaded and Scene B not loaded

At some point in Scene A I trigger a blend from camera A1 to camera A2 and I trigger the loading of scene
B. Scene B is loaded with all of its virtual cameras disabled.

When triggered, the blend starts correctly, but it is interrupted when scene B is loaded. The camera snaps to virtual camera A2 instantly. The blend value disappears from the "live blend" field in the Cinemachine brain.

The blending works fine if the game starts with both scenes loaded at the same time.

What am I missing?