1031 and or 121 exclusion on primary residence

Can someone give me the low-down on 1031 exchange and how it can apply to a primary residence? From my understanding if you have no intentions of making your primary residence into a income producing rental for at least 12 months the 1031 will not apply. And only be able to take the 121 exclusion as we have plans to sell our home and will be in between homes for a bit( traveling around the country in 45ft motorhome with family for the next year). So my original thoughts before reading the tax language was to try and find a rental property to replace our primary residence. Thanks in advance, Scott