In this article, https://dinonline.org/2012/09/16/accepting-yom-tov-early/ one of the sources cited is Minchas Yitzchak 1:42. I was unable to find any reference to this topic there.
Thank you in advance.
Gemar Chasimah tovah.
Answer:
Please see Minchas Yitzchak 10:41, at the beginning of the teshuvah. Thanks for pointing out the mistake.
Best wishes and Gmar Chasimah Tovah.