The festival offering at the season of first-fruits was to be offered on one day only; and was the same with that of the new moon and Passover. It nearly though not entirely accords with the sacrificial offering prescribed in Leviticus 23:18 ff.
Related Commentaries of Numbers 28:26
Numbers 28:26-31
26 Also in the day of the firstfruits, when ye bring a new meat offering unto the LORD, after your weeks be out, ye shall have an holy convocation; ye shall do no servile work:
27 But ye shall offer the burnt offering for a sweet savour unto the LORD; two young bullocks, one ram, seven lambs of the first year;
28 And their meat offering of flour mingled with oil, three tenth deals unto one bullock, two tenth deals unto one ram,
29 A several tenth deal unto one lamb, throughout the seven lambs;
30 And one kid of the goats, to make an atonement for you.
31 Ye shall offer them beside the continual burnt offering, and his meat offering, (they shall be unto you without blemish) and their drink offerings.