Ibn Ezra on Numbers 28:10

בשבתו. שב אל יום השבת אע"פ שנמצא כל שומר שבת מחללו והטעם כל שבת ושבת כמו יום ביומו: OF EVERY SABBATH. The vav suffixed to the word shabbat¹³The reference is to the vav in the word shabbato (every Sabbath). refers to the day of Sabbath.¹⁴Shabbat is feminine. Thus Scripture should have used the term shabbatah if the reference was to every Sabbath. Hence I.E.’s comment that the vav refers to the word yom in verse 9, which is masculine. Thus according to I.E. we should render shabbato (every Sabbath) as every Sabbath day. This is so even though we find the word me-challelo¹⁵Rather than mechallelah. (from profaning it¹⁶The reference is to the Sabbath. We thus see that Scripture treats shabbat as masculine.) in Every one that keepeth the sabbath from profaning it (Is. 56:6). The meaning of be-shabbato (of every Sabbath) is, every sabbath and sabbath. Compare, yom be-yomo (daily) (Ex. 5:13).

על עולת התמיד. הטעם אחרי התמיד שישים עליה עולת שבת: BESIDE THE CONTINUAL BURNT-OFFERING. This means after the continual burnt offering. The Sabbath burnt offering shall follow it.¹⁷Literally, he shall place the Sabbath burnt offering upon it.