How long is insulin okay in the reservoir?

Long story, short-- how long is insulin good in the reservoir? She uses Apidra, if that makes a difference. I've always changed it out with every site change because I remembered hearing that it goes bad faster in the reservoir than in the vial. Is that true?

 

Here is an article that states it is good for 7 days in the cartridge on the pump because of heat from the body.
http://www.diabetesmine.com/2013/02/thinking-twice-about-using-apidra-in-insulin-pumps.html

 

Um, I don't think that article says that for Apidra at all.

 

Yes, your right. It is for novolog and humalog.
From the article:
It wasn’t until several years later — 2009 for Novolog and 2011 for Humalog — that the regulations were increased to three days for insulin in a cannula, and seven days for insulin in the pump reservoir (presumably because insulin degrades with heat exposure, and the body is quite warm)

This does not seem to be the case for Apidra.

 

Longer story-- I'm going out of town and my kids will be with my family. I will be gone long enough that Charlotte will need one site change while I'm gone. I usually change out the reservoir with every site change. But I'm thinking if I just filled it with more insulin and left it for the 6 days that it would make the site change that much easier if my sister doesn't have to worry about changing out the reservoir too. The other option was leaving a prefilled reservoir with her so she didn't have to fill it. Is it a temperature issue? Or something about being inside the plastic reservoir for too long?