443-438-1322

Turned off voice mail and let it ring till they give up.

This number called our business today at 1042 hours.  The caller ID said it was a "wireless caller" so I thought it might be one of our customers.  When a recording began, "If you're a business owner..."  I slammed the phone right back down again.

You are correct - to a point.  We are a business and we do not do business in Maryland, nor do we have friend/relatives in the north east USA.
Should we ever develop contacts in that area code, we will simply "invite" their phone number(s) into our D**it**e call blocker.
Problem solved!
FYI: I did NOT imply that "everyone with a 443 number is bad..."

from a phony cell phone #.  pressed 1,  lady answered and hung up on me.

This is our 3rd call from these criminals.  Their call was blocked BEFORE they robodialed our phone number.
We are a bit more proactive that most folks.  
We have both a call blocking phone and a call blocker on our home line.  The call blocking phone blocks the local calls such as 714, 323, 310, 213, 818, 661.  
Our Di*it**e Call Blocker blocks area codes from across the USA.
We have hundreds of local phone numbers blocked by our P**a**nic phone (blocks 250 full numbers) and the Di*it**e call blocker blocks entire area codes.  Currently, we have over 150 area codes blocked.
When you block and entire area code, potentially, you block 6,000,000 to 8,000,000 phone numbers.  We like that!

Create a contact name #1 (Mine is called Don't Answer or DA1) and fill it up with your blocked callers: make sure each one is labeled "work". When you need  or want to, create contact name #2 and fill that one up with "work" blocked numbers. Keep it going as long as you want. IT sucks to have to do this but it's a great work-around.

Harassment on my business line from these previously blocked number.

Rang wireline. Call blocked.