Mervin

You still get reported for having a noisy can, but if you take part in the rectification scheme, you get 14 days to get your bike road legal and have it inspected by a DOT garage.

You have to get the rectification notice stamped by the garage and then you send this to the cop shop.

If you fail to do this within 14 days, you'll get summonsed/fined/etc for the can.

If you comply with the rectification notice, any report of you and your noisy can gets scrapped.

So, in theory, you could just bung your standard can back on and get the bike inspected, job done. Get home, and put your noisy can back on. However, next time you get stopped, there will be a record of the initial rectification notice inssued and there's a decent chance you'll just get reported without the rectification scheme being offered a second time.