@Johnnn

There is defintely steps that can be taken to improve the connection quality, however, this behavior could be a result of a few factors.

1) I would first try to remove the AP from the network and verify if the internet drops still occur on your client devices. 

2) If the behavior persists with one router, I would troubleshoot this behavior before adding an AP into the network.

2) If the behavior only happens when you are distant from the router, make sure that your device is successfully changing between the wireless bands. You can verify by performing a speed test, then restarting the wifi on your phone, and then performing another speed test to compare.