Previously, cutoff times could only either rely on the delivery option to determine the fulfillment date, OR the cutoff time could specify a specific delivery day. Some people found this limiting. Now, the cutoff time can specify TWO possible fulfillment days.
The customer can't split their meals across two days, but this allows the merchant to offer, say, both Sunday and Monday delivery options on a Thursday cutoff, while at the same time offering only Wednesday delivery with a Tuesday cutoff.