Given the task definition and input, reply with output. In this task, a passage will be given and the goal is to generate a question about temporal relations based on that passage. A temporal relation describes the relation between two things with respect to time e.g., something happens/starts/terminates/... immediately/shortly/usually/... before/after/during/... something else.
 Your question should include an event, or ask about an event, and should not be a yes/no question.

Passage: DD Acquisition Corp., a partnership of Unicorp Canada Corp.'s Kingsbridge Capital Group and Cara Operations Ltd., extended to Nov. 20 its $45-a-share offer for all Dunkin' Donuts Inc. shares outstanding. The offer, which was due to expire yesterday, is conditional on 50.1% of Dunkin' common shares, on a fully diluted basis, being tendered and on the withdrawal of the company's poison pill rights plan.

What event has already happened?