Tp link should consider the need to allow for as easy away as possible to change the Wi-Fi password on their routers. 

Right now if you have a lot of Wi-Fi devices there's no way to change your Wi-Fi password without either making the job take days or making all your Wi-Fi devices unavailable until you finish the switch. 

Being able to change your Wi-Fi password periodically it's a Smart security step. I would hope that tp link would agree with this. 

The easiest way I can think of is to allow the router to be given a second SSID setup. One that isn't limited like the guest network is or the iot network.

Then you could set that up with a new SSID and a new password at one at a time go through all your devices and move them from your current Wi-Fi SSID to the new one. That way you'd only be bringing one device offline at a time and then getting it right back online. 

When you're done this would now be your main Wi-Fi SSID and the old one would be your alternate and nothing would be connected to it any longer. 

Having only one primary SSID means as soon as you change the password every device on your network can no longer connect. If you have 100 or 150 devices it's going to take you a couple of days to get around to all of those things and make changes. 

I hope someone from TP Link will see this, understand the problem, and come up with at least some way to do this without knocking all your Wi-Fi devices off the internet for days