When we say Birkas haMazon (blessing after meals), the second blessing contains thanksgiving Node L'kha with the addition for Chanukah and Purim and the third blessing of Yerushalaim contains request for Avodah/Service in the Temple with addition of Ya'aleh v'Yavo on Rosh Chodesh and Moadim.
In the last 3 blessings of Amidah the order is reversed. We first request for Avodah in the Temple with addition of Ya'aleh v'Yavo on Rosh Chodesh and Moadim. Afterwards we say thanksgiving Modim with the addition for Chanukah and Purim.
What is the reason for such a reversed order?