These two teams, Patoranger and Lupinranger both count as the 42nd Super Sentai Series. Even if that is the case, these two are considered to be separate works with intersecting storylines that take place in the same world. The two shows will air alternately from week to week until they reach episode 20 in which the storylines of the two shows will converge, giving us one single, solidified story.
At the toy side of things, the two toylines are essentially separate until the two shows will converge into one show. The show's 4th quarter toyline will combine and interact with the toys of both teams. Finally, as for how the two shows will likely converge into one, one of the Lupinrangers is actually an undercover spy for the Patorangers. It is likely that this cast member will be prominently featured on both shows.
[Source: Toku Insider]