Yes, the integration stores the username & the password until the next reboot to make it simpler to add multiple devices without re-typing the credentials. Each individual config entry (i.e., individual device) will only store a hash from the credentials that keep working as long as the username & the password remain unchanged.
I don’t have this device, but I haven’t seen this issue on any of my test devices that use the authenticated protocol, so it’s hard to say what could be the problem.
Thanks for the reply! I’ll try again and see if it was user error. I am guessing it was. 
I went to 2024.2.0 and tada, it also discovered one of my new EP25 devices. I should have restarted Home Assistant, but instead I just plugged in the other 3 EP25 devices, then added them 1 by 1 by IP address (that I looked up in the Kasa app under Device Info).
Yay! I wasn’t a fan of the authentication for the first one I added. I’m glad it didn’t keep asking for authentication for my 2nd, 3rd, and 4th EP25s as I added them.
I did notice that the new paddle type of Pico Remote doesn’t get recognized correctly yet, details here:
This was user error. My device had poor wifi signal and was dropping off because of that. After getting better signal to it, I haven’t had anymore issues even after unplugging it and plugging it back in. Thanks!
I don’t see alot of posts where the EP25 setup was done without the KASA app. Although the python-kasa readme documents a procedure for setting up a TP-LINK device without the cloud it doesn’t seem to completely work for me. Has anyone attempted to set up an EP25 (without cloud) AND integrate it successfully into HA?
Using the python-kasa CLI I can discover my virgin EP25 and do a ‘wifi scan’ successfully but ‘wifi join’ will fail.