How to Suspend Front End of Blog When Expires

Hi Guys,

Need help on 2 things:

1) Will the front end show a "Suspend" page if the user did not pay ? I have gone through the forum and found this post https://premium.wpmudev.org/forums/topic/pay-to-blog-suspending-websites-who-havent-paid

I am not sure if I should place the codes in every theme enabled in my site or just the main site? The other thing, if I were to upgrade the themes I will have to remember to place the codes again. Is there a file that I can create (similar to that of bp-custom.php) in the plugin to suspend the front end when blog expires?

2) Currently, the plugin only exempts the main site from payment. Is there a way for me to include other sites from payment other than extending the period?