The first episode of the special aired last February 24th, with the second episode airing on March 3rd at 10am on the TTFC app. For fans who are not part of TTFC, you can still watch this special as this is included in Lupinranger vs. Patranger's 4th/final Blu-ray Collection set, which is set for a June 12th release.
[Source: Akiba Souten via Daisuki Toku]