Steps to reproduce:

1. Create new project and add cube
2. Set rotation to 0, 0, 330
3. Open animation window, create new animation and move to keyframe at 0:30
4. Using rotation transform handle, rotate cube to around 0, 0, 350
5. Inspect first keyframe and notice that rotation is around 0, 0, 180

Reproduced with: 5.4.0b21, 5.4.0b24, 5.5.0a2
Not reproducible: 5.3.4p7, 5.4.0b20