1. I believe it’s OK to skip breakfast once a while. There’s a weekly 5:2 diet and a weekly 4:3 diet — see https://www.healthline.com/nutrition/the-5-2-diet-guide
2. For some people, it’s safe to skip breakfast for years. See fasting can be healthy #breakfast/lunch skip

The cited BBC program echos my experience that skipping breakfast is the easiest fast, not totally bad or dangerous.

• xp: in Macq, I spent about 1.5 Y skipping breakfasts and delaying lunches. In RTS I did similar things for most of the 12M. When I did eat breakfast, I ate mostly chia seeds, milk and fruits. Occasionally I eat some peanuts.
• xp: the empty-stomach sensation in the morning is a very common (sometimes eerie) sensation, but not a real problem in my experience. I think some almond milk, half a slice of bread or a small biscuit can remove this sensation though I am cautious about the consequences [1]. Actually, the intermittent fasting diet encourages us to try and live through this sensation without any food. Presumably, every participant needs to get used to this mild hunger sensation in the stomach. For some, it’s actually easy to get used to.
• xp: The hunger is 3 times worse in the afternoon/evening than morning. However, no need to feel guilty if you do eat a heavy breakfast.
• xp: when I skip breakfast, I tend to feel not hungry after 12 noon, which makes it much easier to delay lunch. That’s why I don’t eat in the morning unless really hungry [1].
• [1] +! craving]morning, should I eat raw veg@@ No