Well, apparently you did, since you wouldn't run into error 23911 if you didn't. There's limits per 24h, but also (larger) limits per week and per month, so if you use up the 24h limit every day in a row you'll start running into the week / month limits.

If you tell me the serial number of the WiiU console the NAND is from, I can check the server logs and see what the current limits are.

Not really, but I've hidden it from the post anyways if you're worried about that.

I checked the Wiimmfi logs, there are indeed more time limitations than just the 24h profile limit. Exhausting that one a couple days in a row triggers another weekly limit, and exhausting that can run you into another monthly limit.

Ultimately, Wiimmfi wasn't really designed with this situation (sharing one NAND with a bunch of different people) in mind - so everyone using the same NAND will share all profile creation limits, causing issues like you're encountering right now.

I can't see the exact timing unfortunately, but in your particular case it will take something between 2 and 7 more days until you can create a couple more profiles which should be enough for 4 people. Though, don't go around and make more test profiles to see when that timer is up. Just tell your friends to try again every day or every two days until they all have profiles.

Creating a bunch of random test profiles just to delete them again wasn't really a smart move - as that's exactly what these limits are intended to prevent.