I see what you mean - the picture helps - I thought the printing was off-grain - which it often is on panels.
At first glance, it does seem to be square - but - - - - - -
If it was mine - and I wanted to maximize the white/ivory area, I might make a 4-7/8v(see-through) template and use that to fussy cut around each square - and then do the sashing/fudgeing strips to bring the squares up to a more easily manageable size to make stars.
Or I might just decide to use it as a whole cloth piece and call it good enough.