Sign boundary query

1
I came across the following quote from Bernadette Brady in a 1997 paper on castle besiegement (to predict contests):
Note: A zodiac sign is considered to be from 1 to 30 degrees. Thus a planet is not in a particular zodiac sign until it has reached 1 degree 00? of that sign. Thus Jupiter at 00 15?of Capricorn would be considered as 30 degrees 15? Sagittarius and thereby still in rulership.
Prior to reading this I always considered the boundary to be "black and white" - i.e when a plant crosses 0.00 into the "new" sign then that is considered to be the planets sign. This is of particular interest to me as I have two planets in such a situation (Sun 0.27 Aquarius, Mars 0.40 Taurus). What do members of the forum consider as the sign boundary? Is there a source such as Bonatti or Valens?

2
Bernadette Brady is a modern astrologer who uses traditional astrology, as you can see her comment that traditional astrology is based on "right wing" thinking... Specially in writings from that time, I would not follow to the letter what she said about the tradition, many waters have passed the bridge since then.

A Zodiacal sign is NOT considered from 1 to 30. It is considered, traditionally from first degree to 30th degree, what may be the source of confusion. There were several discussion on the topic very recently, you can see the forum archives.

So the first degree of Aries would be from 0d 0m 01s to 1d (including).

There are sources that say that a planet in the last degree of a sign and in the first degree of another are afflicted, weak, etc. But affliction is very different to say that "they are still in Sagitarius". This is modern thinking that says that sign boundaries have "orbs", mixed with traditional sources.

A planet is either in a sign or in another. If a planet in the first degree was still in the previous sign, the ancients could easily have changed the boundaries to fix this!
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