Till when one cane overwrite the H1 Visa

My H1 Visa is being applied this year 2014, so one way you told to override the status is to go outside of country and then enter on the L1 Visa.

One question regarding this, till when I can do so?..My current L1 visa is valid till Jan-2014, so can I override the new H1 visa even in Dec-2013 with my L1-B visa. Please suggest.