Stop and modify a Cyvle during animation

[Imago]

I made a walk cycle, but now I need to make the char stop at a certain point and rise its arm... But the arm jumps to the position in one single frame!
In previous versions, the cycle was automatically stopped at new keyframe and the char smoothly go to the final position...
There are some new feature that I didn't know?

[funksmaname]

select the arm bones (or points) and investigate the red lanes of your timeline... if you delete the one one frame before the up (or move it left) you will get a transition. perhaps somehow you must have added keys to parts of the body you didn't want keyd?