Waxing About Oil

It is well-known that there is a hiddur mitzvah to light a Chanukah menorah using olive oil. After all, the miracle of the menorah occurred with olive oil. Rav Sholomo Zalman, zt’l, is not sure, however, if this hiddur mitzvah trumps the well-known dictum of “zerizim makdimim l’mitzvos”—mitzvos should be performed at the earliest opportunity.
Suppose someone has only wax candles available and the time for Chanukah lighting has arrived. He is expecting a delivery of olive oil. Should he wait until the olive oil is delivered or light immediately? Rav Shlomo Zalman, zt’l, left this question unresolved.
A homeowner decides to hedge his bet. He decides to wait 15 minutes for the oil. When the time passes with no delivery, he fills up his menorah with wax candles. As soon as he finishes the setup, the oil is delivered. Should the homeowner remove the wax candles from the menorah and replace them with oil? The Shevus Yaakov (1:36) says he should not. Once he already designated the candles for the mitzvah by placing them in the menorah, it would be a degradation of a mitzvah object to remove them. The homeowner should therefore light that night with wax candles and the next night he should resume his custom of lighting with oil.