If you've picked up Rayman Legends on PS Vita or held off on account of content missing out from this particular version you're in for some good news. Ubisoft have confirmed that the extra 28 invasion levels are now available as a free update on PS Vita.
"The free patch for Rayman Legends on the PS Vita is now available! The patch includes 28 Invasion levels and leaderboards. These trap-laden, enemy-festooned timed levels will push your skills to the limit, while increasing total number of Teensies on the PS Vita to 700."