I hope you find this information useful. My recommendation is that if
you have got other cats coming into your home and you want to put a
stop to it you are best not waiting and simply order the original Pet
Porte microchip cat flap now. Later on you could easily change them
over if you decided that you did want any of the new features.
It's all explained on the Smart Flap FAQ at http://www.microchipcatflaps.co.uk/smartflap.html