A California woman beat Honda in small-claims court last week, receiving nearly $10,000 in damages after getting lower-than-advertised fuel economy in her Civic Hybrid. Early next week, we may have a better idea of how many people intend to follow her lead.

A key deadline arrives Saturday that affects all U.S. residents who bought a Civic Hybrid between 2003 and 2009. Those owners are considered part of a class-action lawsuit regarding the fuel-economy issue – unless they opt out of the case by Saturday.

Owners who opt out will not be entitled to the expected settlement of up to $200 and a coupon off their next Honda purchase. But opting out preserves their right to go it alone in court, as Heather Peters did, and seek a more substantial payout.

In order to opt out, owners must send a certified letter to the settlement administrator postmarked no later than tomorrow. More information can be found at hchsettlement.com.

Automakers, legal experts and consumer-rights advocates are all keeping an eye on what happens in the class-action suit, both in terms of how the case is settled and how many people forgo a smaller settlement with the intent of filing individual cases.