When Yom Tov begins on Wednesday night (in Galus), the eruv tavshilin ceremony is performed on Wednesday and when Yom Tov begins on Thursday night it is performed on Thursday, in each case by the head of the household.
If one is unsure whether or not a particular food item is subject to the penalty of chametz she'avar alav hapesach, one is permitted to derive benefit from the item, though it remains forbidden to be eaten.
The survey itself is skewed, written in a style that clearly wants to advance identifying publicly with flags representing grave sins. This is dishonest and unethical in itself.
If one perceives that, rather than seeing his own decisions as determinative of his fate, Divine providence is guiding the result, then considering that there’s a halachic mandate to follow professional medical advice (see Taz, YD 336), the conclusion is most clearly in line with the dominant medical consensus.
Questions and answers with Rav Hershel Schachter shlit”a, regarding situations arising from the coronavirus crisis. Transcribed by Rabbi Pini Dunner (assisted by Michael Bernstein). This transcript has been approved by Rav Hershel...
He points out that medieval Ashkenazic authorities never saw an olive. Olives do not grow that far north; they only grow in the Mediterranean region.