Got this from Kohl's today:
Kohl’s is testing something new with the upcoming February Credit Event. Kohl's Cardholders will now receive an unique code by email and in their mobile wallet with their 30%, 20% or 15% off with Kohl’s Card offer. This offer code can be used 5 times from 2/5-2/15.
We will not have a general 30% off code to promote. Please direct customers to look for their unique offer code in their mobile wallets when checking out. This will run similar to our Mystery Offer.
Please also try to keep customers from posting their unique codes as we do not want other customers having poor experiences with expired codes.
So it sounds like the days of using the 30% off code even if you weren't mailed the 30% are over, at least for now. They are probably going to see how that affects sales and if those who didn't get a 30% just won't buy anything instead of using their lower-% coupons.
It looks like you are able to add codes sent to other people to your Kohl's Wallet so if you know someone who gets a 30%, they can share the code with you and it appears both of you can use it (up to the max 5 times total).
If there is interest we could set up a thread where those who have "extra" uses of their 30% code that they won't be using could let the rest of the forum know and those interested could PM them to get the code in case they didn't get a 30% this time.
Update: For now let's just use this thread. If anyone has a 20% or 30% code they won't be using all 5 uses for, post here and anyone interested can PM you about it. Don't post the codes in the thread - keep it in PMs so lurkers don't take them.