Al-Tawalbeh et al. (2020) bracketed the date of the first theater earthquake to between 97/98 CE and a dedicatory inscription dated to 260/261 CE. Although Al-Tawalbeh et al. (2020:10) noted that "a definitive judgment on the time separating the first earthquake occurrence from its subsequent reconstruction" is "difficult to support", restoration efforts memorialized by the inscription suggest that the earthquake likely occurred close to the 260/261 CE date — within a few decades. Numismatic and epigraphic evidence indicates that the city was fairly prosperous from the later half of the second century CE into the first half of the third century CE and thus capable (and willing) to convert their theater to an amphitheater fairly quickly after the damaging earthquake.

Al-Tawalbeh et al. (2020) discovered only a few recent earthquakes in the earthquake catalogues close to the 260/261 CE date — in 233, 242, and 245 CE. However, these all appear to be false events originally propagated from Willis (1928)’s first uncorrected catalog, which misdated earthquakes reported by Arab chronicler As-Suyuti by ~622 years due to a failure to recognize that As-Suyuti’s dates were reported in the Islamic calendar (A.H.) rather than the Julian calendar. Ambraseys (2009) reports a possible earthquake in Palmyra, Syria in 233 CE based on an inscription. However, Palmyra is 310 km away from the theater at Capitolias, so it is doubtful that an earthquake could have caused heavy damage in both places. Hence, this archeoseismic evidence points towards a previously unrecognized earthquake not reported in the earthquake catalogues and not mentioned in any extant historical source that is currently known.