Tosefta к Эруви ́н 6:11

Kohanim and Levites that were standing around by the threshing floor, and other Kohanim came and stood [with them], they (i.e., the newcomers) cannot take [the priestly gifts] from their hands. Said Rabbi Shimon ben Gamaliel, Kohanim used to comport themselves generously, to not send away their brothers empty-handed, but took from their [own] share and gave to them. Rabbi Shimon ben Elazar says, if they came before the cycle [of donations] was repeated (=תחזור חלילה, cf. Y. Eruv. VI.3.2), they stand there until the following (=עקוב, see Jastrow) [circuit] and they take [their portion of the priestly gifts at that time].