It seems that a problem from GC 1 is still here in GC II: the ETA for a research incorrectmy take into account the free research generated the previous turn.

Here it is how to spot it:
Take the Thalan, on gigantic and set them 50% research (by dropping social production bonus for example).
The first turn, change slider to get only 1 BC in research and select the xeno factory construction. You will see that you need 816 week.
Then put 100% spending on 100% research. your planet will produce 36 BC but you will pay only 27.
Hit turn.
set spending to 0. You will see an ETA of 87 week.
Hit turn
The ETA will be now "never". Change spending to generate only 1 BC in research, your ETA will be 780 ( =816 - 36)

And 780/87 roughly equals to 9 which correspond to the free research generated the first turn