I got strange flickering, I thin this is low settings of global illumination. What lighting do I have there?
Illuminating texture of sky (sphere), sun (deformed plane) and one spot light.
Could you help me solve this problem ?
Is there any render settings I can decrease to make rendering time shorter?
I know I should google it and try render it with different settings, but it takes so long. Now rendering whole animation takes 18 h, and I need to deliverer that tomorrow.
Yes, it's almost certainly the low GI settings you're using. Unfortunately getting the right balance between speed and quality is a time consuming process of trial and error. I would suggest you read the help section on Irradiance Cache at minimum.