A brief history of the "pre-staging" options: traditionally, a "Set Color" command will set a bulb to a specific color, while also turning the bulb on if its state at that moment is/was off. The "color pre-staging" option was added more recently to some drivers, allowing only the color information to be sent, while otherwise keeping the bulb in its current state (on or off). Not all devices or drivers support this.
So, as you may know, what this means is that if you have this option enabled, if you want to turn a bulb on to a specific color, a "Set color" command alone is not enough. You must also issue an explicit "On" command. Most apps are built around the traditional behavior of the "Set Color" command, where the added "On" isn't necessary. Simple Automation Rules appears to be one of those apps.
My preference, given the oddity of this behavior (the fact that many apps aren't aware of it--and the fact that it's not consistently supported by all devices), is just to avoid the setting. 
If you have a reason for enabling it, I'd consider other possibilities--for example, if the app you're using to turn on the lights in the first place can make the decision about what color/CT to set it to (based on time, mode, or whatever restrictions/conditions you're able to configure), then that's easy enough, but I suppose that will depend on exactly why you wanted to do this in the first place. If you do want to keep pre-staging enabled, then I think you'll need Rule Machine instead of SAR for this automation. You can then use a "Set Color" action followed by an "On" action.
(The "level pre-staging" options you may also see are similar, by the way, except of course affecting "Set Level" rather than the color-related commands.)
