DatePlus

DatePlus[date,n] gives the date n days after date.

DatePlus[date,{n,step}] gives the date n calendar steps after date.

DatePlus[date,{{n1,step1},{n2,step2},…}] gives a date offset by ni steps of each specified size. 

DatePlus[n] gives the date n days after the current date.

DatePlus[offset] gives the date with the specified offset from the current date.

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