Amend ALL user's SMTPs

Hello everyone, 

We're having a bit of trouble at the moment within our business

Using the Exchange Management Shell, i want to write a script which takes all the SMTPs for a mailbox, and writes"_DELETED" to the end of the name.

For instance, "joe.bloggs@blah.com" would become "joe.bloggs_DELETED@blah.com"

This needs to work for ALL SMTPs on the user's account (it's a big contract, and some have 20 odd each)

We are in the process of deleting a number of accounts, and doing this manually would be very time consuming. 

Any ideas would be great!