Section 4 of ICA : Section 4: Communication When Complete

Explanation using Example

Imagine you want to sell your old bicycle and you send an email to your friend offering to sell it for $50. This is a proposal. Once your friend reads the email, the communication of the proposal is complete.

If your friend then replies to your email agreeing to buy the bicycle for $50, the acceptance is complete against you, the seller, the moment your friend hits 'send' on that email. It's complete against your friend when you read the email and learn about the acceptance.

Now, if you change your mind and send a text to your friend to cancel the offer before your friend has sent the acceptance, the revocation is complete against you when you send the text. It's complete against your friend when they read the text and learn about the revocation.