the Anniversary Feasts were Seasons of Sacrificing
Source: TTT
1 Samuel 1:3
Year after year Elkanah would go up from his city to worship and sacrifice to the LORD of Hosts at Shiloh, where Eli’s two sons, Hophni and Phinehas, were priests to the LORD.
1 Kings 9:25
Three times a year Solomon offered burnt offerings and peace offerings on the altar he had built for the LORD, burning incense with them before the LORD. So he completed the temple.
2 Chronicles 8:13
He observed the daily requirement for offerings according to the commandment of Moses for Sabbaths, New Moons, and the three annual appointed feasts—the Feast of Unleavened Bread, the Feast of Weeks, and the Feast of Tabernacles.