Hello 

I am new to this forum..

I am using Archer C1200 provided by Unifi as part of my upgrade to 300 MBPS Plan. 

My house two floors, each one floor size of about 1500 sq. ft.

Earlier I was on 100 MBPS plan and my Apple Air Port Extreme and Apple Air Port Express worked perfectly as a pair to provide me whole house internet. The Air Port Express has wired Ethernet input coming from the AirPort Extreme output ports.   The SSID and passwords for both routers were same and the connectivity was very seamless.

My apple devices will pick up the stronger of the two routers and provide me seamless connection as I moved from one floor to another.

Upon upgrading (?) to 300 MBPS I found out to my dismay that the Apple Air Port Express has a maximum limit at 100 MPBS.  Air Port Extreme can go higher though.  So my beautiful soltuion isn't working anymore.

I want to know .. Is there a TP Link product which can do above explained functionality ..

I guess, I need add a 'range extender' or 'access point' type of device. I need a set up  which should swich device connections to the stronger of the two WiFI networks as I move from one floor to the other.

I tried to work this myself with one TP Link Rounter (Archer C1200) and moved my AirPort Extreme Router to upper floor. Archer C1200 is at Ground floor.  I gave same Wifi SSID and passwords to the two routers.. both routers work fine and provide me 300 MBPS.. but the switch from one to another is not automatic.  When I go from one floor to another,  I have to manually change the Wifi Network.. which isn't ideal for me.

Can someone help me. ?