How to use Lock to AP function on TL-WR802N?

According to our survey, customers have an idea on TP-Link router TL-WR802N and want TL-WR802N working as client mode or range extender mode to stick to one wireless access point all the time even though there has another access point having the same wireless settings. To meet this kind of need, TP-Link releases a new firmware 190218 which has Lock to AP function.

Scenarios:

1). Two access points which have the same wireless network name and password.

2). TL-WR802N is connecting AP a to have internet access as client mode/range extender mode; (TL-WR802N V4 190218)

A. If we do not enable Lock to AP function on TL-WR802N when configuring it as client mode or range extender mode via Quick Setup or Wireless—>Basic Settings:

TL-WR802N will switch its connection to AP b when AP a is powered off or goes down, and it will not switch back to AP a if AP a works again unless AP b stops working as well.

B. If enables Lock to AP function on TL-WR802N when configuring it as client mode or range extender mode:

TL-WR802N will not switch its connection to AP b and stick to AP a even though AP a is powered off or goes down, and it will only reconnect to AP a when AP a works again.