Further to the question: Can there be portals in the Astral Plane that lead to the Elemental Planes , I wanted to ask does Astral Projection spell fail if cast while on the Elemental Planes or Material Echo Planes (Shadowfell, Feywild)?
I had assumed that the silver cord of an Astral Projection spell required some means of accessing the Astral Plane in order to function. Accordingly, because 1) the Astral Plane and Ethereal planes are entirely different planes, only sharing the fact that they are both Transitive Planes and 2) just as the Ethereal Plane does not border the Outer Planes (explicitly in the spell description and implicitly elsewhere), it appears that the Astral Plane does not border the Elemental Planes or Material Echo Planes (implicitly) and 3) the Etherealness spell explicitly indicates failure if the caster is on the Ethereal Plane or a plane that does not border it and 4) the Astral Projection spell description in the PHB appears to be improperly worded regarding access to various planes in comparison to the description of Spells in the Planar Travel section and the Astral Color Pools table both in the DMG (hence the initial reference to the previous question posted regarding that discrepancy) I was wondering A) if I was missing something RAW and B) if RAI it was considered that the spell description (explicitly mentioning failure only when the caster is already on the Astral Plane) was considered an oversight.
According to the Etherealness spell (PHB p238) :
This spell has no effect if you cast it while you are on the Ethereal Plane or a plane that doesn't border it, such as one of the Outer Planes.
According to the Astral Projection spell (PHB 215):
You and up to eight willing creatures within range project your astral bodies into the Astral Plane (the spell fails and casting is wasted if you are already on that plane).
And later in the same spell description:
Your astral form can freely travel through the Astral Plane and can pass through portals there to any other plane.
However, according to DMG in the description of relevant planar travel spells (DMG pg 46) it indicates the following :
And the astral projection spell lets adventurers project themselves into the Astral Plane and from there travel to the Outer Planes.
Accordingly, for both RAW and RAI, does Astral Projection spell fail if cast while on the Elemental Planes or Material Echo Planes (Shadowfell, Feywild)?