Pallas orbits at about 2.77 astronomical units with a period near 4.6 years, so it averages roughly four and a half months in each sign, with a retrograde loop each year around opposition. Its eccentricity is high for a main belt body, about 0.23.
The number that matters for astrology is the inclination of about 34.8 degrees, the steepest of any large asteroid. The zodiac as the ancients drew it is a band about eight or nine degrees either side of the ecliptic, wide enough to contain the Moon and all seven classical planets. Pallas leaves it entirely. For much of its orbit the body is tens of degrees north or south of the ecliptic, far outside the twelve constellations, and it can pass within a few degrees of the ecliptic poles as seen from Earth.
So a Pallas placement is a longitude and only a longitude: the projection of the body onto the ecliptic, taken as though it were there. That is a legitimate coordinate and every asteroid ephemeris supplies it, but it should not be confused with the body being in the sign. Pallas is never seen among the stars of the sign it is reported in.
The same projection is applied to every body in a chart, and for the Moon at five degrees of latitude or for Vesta at seven it is a small correction. For Pallas it is not small, and it is the reason a reader should treat its sign placement as a convention rather than an observation.