2nd class mail 0216 eadc 0370 c9c0

A cryptic message!

After some analysis, I think I have a possible solution:

2nd class mail is likely a reference to the type of postal service used to send the message.

0216 could be a date code, possibly indicating the date the message was sent (February 16th).

eadc might be a coded message or a checksum.

0370 could be a postal code or a routing code.

c9c0 is likely a checksum or a verification code.

Putting it all together, I'm going to take a wild guess:

This message might be a postal tracking number or a confirmation code for a package sent via 2nd class mail on February 16th. The eadc and c9c0 parts could be error-checking codes to ensure the message was transmitted correctly.

Am I correct?