You have a couple of options. First, you can try upping the GI settings. I would definitely reduce the diffuse depth from 5 down to 2 or 1, which will make up for a lot of lost time. I’d also use a wider range between the Min and Max settings — at least a 1:5 ratio. Then I would increase the quality setting substantially, to somewhere 90-100%.
You could also use stochastic mode, which is slow but flicker free.
Or, you could copy the “news network” extrude, convert it to real geometry, swap out the converted object after the extrude animation is done, and bake the illumination on the converted geometry.
And of course you could avoid GI altogether.
hth