Paramount was in similar situation with gi Joe 2, but they still pushed it back. The toys can be recalled/put in stores until June or July.
Frankly, I think atleast 2 movies from March should move to august.
Logan
Kong
Batb
Life
Cover most genres.
Out of Gits, power Rangers, king arthur, 2 should move to august.
Ideally, GITS or Power Rangers should move to Dunkirk and give that movie a tough fight while Valerian should release in August.