Mayor Garcetti has until Monday (March 13th) to sign the BHO/BMO update, although he could sign it as early as today. Once he does sign these new ordinances, the City Clerk must prepared and publish them. Because the ordinances were passed with urgency clauses, the ordinances take effect on the day they are published.
Based upon previous Planning Department ordinances that were passed with urgency clauses, that means the new BHO/BMO/R1 rules could take effect as early as Monday if Mayor Garcetti signs them today. If he waits until Monday to sign them, then it could be Wednesday (March 15th) or Thursday (March 16th) before they take effect.
Here’s a link to the BHO/BMO update that was passed by the City Council:
http://clkrep.lacity.org/onlinedocs/2014/14-0656_misc_3-1-17.pdf
And here is the neighborhood-by-neighborhood changes to the R1 zone that was approved by the City Council yesterday:
http://clkrep.lacity.org/onlinedocs/2016/16-1470_ord_draft_2-14-2017.pdf