In addition to the Haswell CPUs set for Q2 2013 as well as the refresh for existing desktop and mobile CPUs, Intel apparently aims for Q1 2013 as the timeframe for new mobile Celeron CPUs that will be part of the new 1000-series.
According to Digitimes, Intel plans to launch at least four new mobile Celeron CPUs, the 1000M, 1020M 1007U and the 1037U. The "M" parts will feature a 35W TDP and are aimed at mainstream notebook market while the "U" parts are most likely be a part of some cheaper ultrabook lineup. Of course, these new Celeron parts are based on Ivy Bridge architecture and will be joined by the Core i5-3437U and the Core i7-3687 dual-core CPUs.
Orders for most Sandy Bridge based parts, including the Core i7-2600K, Core i5-3450, Core i5-2310, Core i3-2105 and Pentium G440, will not be available after the end of 2012. With the introduction of these new Celeron parts, single-core Celeron 807 and B730 will no longer be available, at least not for order.