Is it possible your Ca was lower than you thought it was beforehand?
I'd be more worried about an Alk overdose than a Ca overdose though. If you think of it that's only about 4-5 days worth of Ca dosing, some people dose a week's worth a time. I think it's better to do it in small increments of course, but it goes to show it's not always catastrophic to have too high Ca in go (within limits of course).
It's possible that the excess Ca just precipitated out of solution though. This can be compounded if your Mg is low. Many times people complain that they can't get Ca high enough and it turns out to be a low Mg issue.
I would check your pump impellers for Ca buildup. That will be where it will accumulate the worst. A vinegar bath ought to fix it all up if there is indeed a Ca coating on them.
FWIW I run my dosing on the Apex using an 8 hour cycle using the OSC function, and I offset the Ca/Alk dosing by 4 hours by making one of them have the pre-off value at 240 minutes whereas the other is at 0, then the on value is however minutes is needed, and the post-off value is whatever the on is taken away from the first two values to make a total of 480 minutes.
I'm tempted to shorten the intervals to make more doses over the course of a day but I haven't put too much thought towards it yet. In fact the only reason for the 8 hour cycle is that I was using programmable appliance timers prior to the Apex and I didn't want to have to adjust too many programs when I wanted to change a dose amount so I picked 3 times per day. I just carried that forward to the Apex so that there wouldn't be a perceivable change to the tank routine.
Anyhow let me know about the impellers, kind of curious to see where this goes. Good luck, hopefully nothing bad happens, pretty sure you're OK but good luck anyhow.
