The Gheranda Samhita describes utkatasana as rising onto the toes with the heels lifted clear of the ground and the seat resting back on the heels, the whole body held high and balanced. It is the closest thing to a standing posture in the classical corpus, and even here the practitioner is on the toes rather than on the feet.
Utkata is a word with a range: raised, elevated, and also fierce, immoderate, excessive. Sanskrit posture names frequently work in that register, describing a quality of the arrangement rather than an object it resembles, and utkata sits with mukta and gupta and bhadra in that smaller group. Which of its senses the compiler intended is not stated, and the atlas does not choose between them.
The Hatha Yoga Pradipika does not carry the posture. Counting across both surviving manuals, the postures performed on the feet number three or four out of the whole classical repertoire, and utkatasana is one of them. That scarcity is the single most consequential fact about the difference between the medieval literature and modern practice, and it is easy to miss when reading the entries one at a time rather than as a list.
The Gheranda Samhita attaches no benefit to utkatasana, which puts it with roughly a third of the entries in the second lesson. That silence is itself informative. A compiler willing to promise the destruction of disease elsewhere in the same chapter, and declining to promise anything here, was making a distinction rather than filling space, and the postures given without claims are among the best evidence that the list was assembled from practice rather than composed for effect.