The creation of ordinary consuls in Late Antiquity was irregular, and after their division in 395, the two halves of the Roman Empire tended to divide the two consulships between them; the office, which had become both purely honorary and quite expensive to hold, sometimes lay vacant for years.
[1] Throughout the 6th to 9th centuries there is ample sigillographic evidence of functionaries bearing the title, usually attached to mid-level administrative and fiscal posts.
[1][2] In the late 9th-century hierarchy, however, as related by the Kletorologion of Philotheos, it was one of the lower dignities intended for "bearded men" (i.e. non-eunuchs), ranking between the spatharios and the strator.
[3] In the Escorial Taktikon, written c. 975, the hypatos appears to be a regular office instead of an honorary dignity, endowed with judicial duties according to Nicolas Oikonomides.
Eventually, with the waning of Byzantine power in the region, these rulers took on more familiar Latin titles like consul and dux, modern duke.