From: Rabbi Akiva Eiger
To: Unknown recipient
Rabbi Akiva Eiger explains that while the individual year calculation for sacrificial animals can be inferred independently from the impossibility of valid tamid offerings on Rosh Hashanah, the precise 24-hour me'es le'es principle requires the verse shnaso. The analysis depends on the dispute between R' Meir and R' Elazar regarding what constitutes a year, with cascading implications for the hermeneutical roles of shnaso and yihyeh. He concludes with an unresolved difficulty from the Rambam in Hilchos Ma'aser Sheni, leaving the matter as tzarich iyun.
Source: Shu"t Rabbi Akiva Eiger §195