When does Paypal billing agreement "expire"?

Question

I'm reading the spec of Paypal billing agreements. It says this

A reference transaction must have occurred within the past 730 days because the ID may not be available after two years. The billing agreement ID does not establish a time frame. It is good until canceled by the buyer.

Does the billing agreement ever "expire"? Is it true that it surely "expires" after 730 days after being created? Is it true that it surely "expires" if there were no transactions on that agreement for 730 days?

Under which conditions exactly does it "expire"?

Answer 1

I was recently looking at this, and I discovered the answer here (https://developer.paypal.com/webapps/developer/docs/classic/express-checkout/integration-guide/ECReferenceTxns/#id094TB0Y0J5Z__id094TB4003HS).

1. Billing agreements never expire until explicitly cancelled.
2. Reference transactions expire after 730 days.