This poll suggests that there will be a disparity between registered voters and likely voter screens, which I'm sure the media will not cover or care about and will present to viewers/readers as "sudden shifts in the race!"
I mean, obviously though. Turnout in even high-profile, competitive primaries is terrible, so of course when only 30% of registered voters vote, you'll have a big difference between RV and LV results.
It's surprising that they show Sanders doing better with RVs than LVs, though. In 2016, it was the opposite (thus his stronger showings in caucus states).