This ideograph is the outline of an area with five rays of light approaching from northeast by east. Depending on the observer's latitude, light would come from this direction early on a summer
morning. Hence, this symbol is the adverb early.
Illustrative Text Reference:
Mohenjo-daro: Seal: M-1793 a: Asko Parpola, B. M. Pande, and Petteri Koskikallio, 2010: Corpus of Indus Seals and Inscriptions: Volume 3,1: Page 51: New material, untraced objects, and
collections outside India and Pakistan: Suomalainen Tiedeakatemia.
The midsummer sunrise at Mohenjo-daro has an azimuth of 63 degrees. It seems likely that the intention was to portray this fact in the symbol.