Related for Yoma 112:8
והשתא דאמרינן לרבי יהודה אין ברירה הא כתיבה אית ליה יום הכפורים נמי נעביד תרי ונכתוב עלייהו
And we asked concerning it: What is the difference touching both directions that it cannot apply, it is only because the principle of Bererah is rejected,<span class="x" onmousemove="('comment',' It being held that the choice the man made between the two Sages on the following day may not have been his choice at twilight on the previous day when the validity of the 'erub must take effect.');"><sup>3</sup></span>
Tosefta Demai
One who purchases [one hundred logs of] wine from Samaritans on Sabbath Eve [that he intends to drink on Shabbat], and he forgot to separate [tithes from it], says, "Two logs that I will separate in the future, behold, they are terumah, and the ten [logs] closest to them are first tithe, and the nine [logs] closest to them are second tithe." And he deconsecrates [the second tithe and transfers its sanctity to money], and he may drink it immediately [relying on the separation that he will perform later], the words of Rabbi Meir. (Sukkah 23b:5, Steinsaltz tr.) But Rabbi Yehudah, Rabbi Yosei and Rabbi Shimon prohibit [this]. They said to him, to Rabbi Meir, "Do you not concede that if the wineskin [may] burst [and therefore he will not be able to tithe it in the future], [and thus] he has drunk from untithed produce?" He said to them, "When it bursts, [I will be concerned]." (Sukkah 24a:6.)
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