An ambitious proposal to expand San Francisco's rent control ordinance to units built through 2024 has been scaled back, but Board of Supervisors President Aaron Peskin says that voters should know what the board's plans are in the event that Prop 33 passes next month.As you may know, Prop 33 is a statewide ballot measure that would repeal the 1995 Costa-Hawkins Act and allow local governments to broadly set their own rent-control ordinances without state limitations. The No on 33 lobby is very well funded and you've likely been bombarded with many, many ads telling you that Prop 33 will make housing more scarce in California, or discourage developers from building, making housing more unaffordable.But, regardless how you feel about rent control, it is one of the ways that San Francisco residents afford to stay in the city, and it is one of the ways that housing remains affordable for many across the state.Supervisor and mayoral candidate Aaron Peskin has been pushing for broad expansions of rent control here for a while, even floating a charter amendment two years ago that would have extended rent control to new construction.His most recent proposal was that the Board should pass a new ordinance, in the event that Prop 33 passes, extending rent control to every rental unit built between 1979 and 2024 — the current ordinance only covers those built pre-1979.As the Chronicle reports, after Tuesday's board meeting, Peskin has scaled back the proposal in seeking support from other supervisors, and the new post-Prop 33 proposal would be expand rent control in the city to units built between 1979 and 1994.Supervisor Ahsha Safai, an opponent in the mayoral race, traded barbs with Peskin about rushing this ordinance through before the election. To that, Peskin replied, "To say we are rushing this is amusing – you either support rent control or you don’t. Let’s let the residents know where we are headed and to come up with a process if Prop 33 passes."Peskin and his team estimate that the expansion, adding 15 years' worth of buildings to the rent-controlled supply, will extend rent-control protections to 40,000 more San Franciscans.Developers say that such ordinances will only discourage investors and development from coming to the city, at a time when the city desperately needs new housing. But development didn't disappear after the previous rent-control ordinance took effect decades ago, and this would just add 15 years' worth of housing stock to the mix.Now, whether Prop 33 will actually pass, after this bombardment of "No" ads, remains to be seen. The most recent polling shows 37% in favor, 33% against, and 30% still undecided. Top image: Still from Peskin's first campaign video