Is it proper to fast on Erev Rosh Chodesh (Yom Kippur Katan), and what are the parameters?

Synopsis

The Magen Avraham and Aruch HaShulchan record the practice of fasting on Erev Rosh Chodesh. Multiple authorities address when the fast falls when Rosh Chodesh coincides with Shabbat or Sunday, and whether one who has been fasting regularly requires hatarat nedarim to stop.

Early Acharonim
Late Acharonim
Lenient
Strict
Lesser cited
Major authority

Discussion

Discussion coming soon.

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