Would it make a difference?
 

If instead of leaving in the primary fermentor for six days (instead of seven) and leaving it in the secondary for eight ( instead of seven)?

What kind of beer are you making? Many people on here (myself included) just skip the secondary all together unless there is drop hopping involved.

Oatmeal Stout. I was actually wanting to do it for carbonation.

I left my oatmeal stout in the primary for about 14 days, using S04 yeast, and it was nice and clear and ready for packaging then.

I'm not sure what you're saying here, about wanting to do it for carbontion, sorry!

It will not matter for a day or two, or week or two. Your hydometer tests will tell you when you can move beer. Take a reading on two different days, when you have the same reading on two days it is ready to move.

Days are not a factor. I don't move it until it reaches the projected FG...;)

And carbing the beer should be done at bottling... or kegging, depending on your setup.

I agree with the others here. You can move to secondary when the yeast is all done. Check your gravity readings to determine this.

racking does not affect carbonation at all. and shifting your racking by a day isn't going to change anything.

+1 hydrometer readings!

Homebrewer_99 is right. I realized this after watching the "Fermenter" at St. Arnolds Brewery do his job. He keeps a clip-board by each fermentation tank and measures gravity and temperature every couple of days to start, then as fermentation nears target gravity, every day.

This reinforced to me that I should be doing something similar and it worked to my benefit. Last month I made an Oatmeal Stout and when I thought it should be done (7 days) and there was no more visible activity, I started taking gravity readings and found out it was not done. Normally, I would have racked it to secondary for clarifying and aging. ;)

The gravity was still around 20 (1.020). I had to drop several more points to hit the target gravity of 1.013. I agitated the yeast and added some "super-ferment" yeast nutrient. I eventually got to 1.014, but I would not have know this if I didn't follow the example I saw at St. Arnolds.

The objective is to make better beer! :mug: