A Toei Video listing shows 51 episodes total for the current Super Sentai series.
Kaito Sentai Lupinranger vs Keisatsu Sentai Patranger will run for 51 episodes, according to a listing from Toei video. Blu-ray collection 4 lists the series running through 51 episodes. The last time a series ran 51 episodes was with 2011’s Kaizoku Sentai Gokaiger.
Previously, series with Blu-ray collection sets were released in sets of four.
The 4th Blu-ray collection is being listed with a June 12th, 2019 release date.
Source: Toei Video