So this may have already been discussed, and I’m not sure that it is an actual bug, but it appears that the time being reduced when adding the Extra Robots upgrade isn’t 10%, 7.5%, and 5%. It seems to be off by a few percentage points more and more with each calculation.

Looking at the game files, the time is shown in milliseconds so I’m wondering if the base speed is in another format and has to then be converted to millisecond time, which in turn is used to calculate the speed increase/time reduction causing the times to appear off.

Below is an example of what I’m talking about. The in game percentages for each Extra Robot Upgrade are in parentheses while the actual percentages I calculated are in brackets next the times in seconds.

Ex. Chassis Assemble
Base Time: 25.75
Extra Robots 1: 23.41 [9.09%] (10%)
Extra Robots 2: 21.91 [14.91%] (10%+7.5%)
Extra Robots 3: 21.02 [18.37%] (10%+7.5%+5%)

What am I missing because this is driving me a little crazy.

I knew I was missing something and figured it out this morning while at work. Was too tired and got fixated on the 10% speed increase trying to make it math out to a linear reduction in time in the opposite direction.

So I was working on creating a formula as well to help me figure out the new time for each upgrade by production slot and I did eventually get this figured out and wrote the below expressions since different slots have different Speed increases based on upgrade. Also, these expressions assume you have bought/installed the previous upgrade.

I under stand what you are doing. The formulas that I have listed above are the ones that I used in my excel sheet. It will show the times for each combination of robots. You may not want to use Robot 1 because it will be to fast but Robot 2 is to slow so if you add Robot 2 & 3 it will give you the time you are looking for or at least get you close.