It will probably be best to ask Honeywell customer service for this question. Here's a link: https://www.honeywellstore.com/customer-service/contact-us.htm
In most residential HVAC the filter should last up to 90 days.
Honeywell air filter are produced in the US and Mexico.
There are 12 filters in a carton. But you can order any quantity on-line at homedeport.com
It is MERV 13. Let me reach out to our R&D guys to make sure i'm right on MERV number. I'll get back to you tomorrow wit the exact number But be advised that this is the most efficient residential air filter we make for The Home Depot. You got the good stuff.
If you dunk it repeatedly. Of course you can't scrub it, but light squeezing hasn't been bad for mine. Remember to spray alcohol on it to disinfect it, that is the best way.