Bhashya
सर्वेषामस्मिन्प्रकरणे उपासनानां गतिरियं फलं चो-च्यते— यदा वै पुरुषः विद्वान् अस्मात् लोकात् प्रैति श-रीरं परित्यजति, सः तदा वायुम् आगच्छति, अन्तरिक्षेतिर्यग्भूतो वायुः स्तिमितः अभेद्यस्तिष्ठति ; स वायुः तत्र
In plain words
For every meditation taught in this whole section, this is the one shared destination and reward now being described. 'When a person who truly knows departs from this world' simply means he lets go of the body. He comes first to Air, stretched motionless across the space between earth and sky, standing there impossible to break through. That very Air, there—
Close to the Sanskrit
For all the meditations set forth in this section, this same destiny and fruit is now declared: 'when, indeed, a person who is a knower departs from this world' means he abandons the body. He then comes to Vāyu; in the intermediate space, spread crosswise, Vāyu stands still, impenetrable. That Vāyu, there—