I'm not sure when this coin was struck
This coin was struck sometime during A.D. 321- 324. "The IOVI coins were issued as part of a coin reform by Licinius in his territories (mints of Heraclea, Nicomedia, Cyzicus, Antioch, and Alexandria) and were reduced in value from 25 to 12 and a half. The coins were worth less because they had little or no silver. He struck these in the names of all the rulers but these coins had no value outside his territory."
On the reverse in the right field is an X over II and an episemon. "The last sign is clearly an episemon, epigraphically employed for S(emis) also." (RIC VII p. 12) Semis literally means half, and the semis coin was valued at half an as.
here is a relevant historical reference to this coin-
DEBASEMENT OF NUMMUS IN EAST BY LICINIUS, 321-324.
"Dionysius to Apion, greeting. The divine Fortune of our masters has ordained that the Italian coinage be reduced to the half of a nummus. Make haste, therefore, to spend all the Italian silver that you have in purchases, on my behalf, of goods of every description at whatever prices you find them. For this purpose I have dispatched an officialis to you. But take notice that should you intend to indulge in any malpractices I shall not allows you to do so. I pray, my brother, that you may long be in health. (Verso) I received the letter from the officials on the eight of the month Pharmouthi."
“Two other fragmentary letters from the same archive (PSI 965 and P. Oslo III. 83) allude to the same reform. In 321 Licinius (308-324) reduced the silver content of his nummus (2.40 gs) and halved its official tariffing to 12.5 d.c. Eastern mints marked the reverses of the nummi with the value mark. The official rate of exchange was probably 1 aureus = 516 nummi sparked off a new wave of price rises until Constantine (306-337) reunited the empire and demonetized the Licinian nummus in 324. See Harl, Coinage in the Roman Economy, pp. 158-166.â€
Source: Letter in Archive of official Theophanes, c. 321 (P. Rylands IV. 607). Translation from L. C. West and A. C. Johnson, Currency in Roman Byzantine Egypt (Princeton, 1944), pp. 184-185, no. 7. See M. Hendy, SBME, pp. 463-64 and R. Bagnall, Inflation in Fourth Century Egypt, pp. 12-15, who redate the papyrus from earlier dates as argued by C. H. Robert and J. G. Milne in Trans. of Inter. Num. Congress, 1936 (London, 1938), pp. 246-249 and C. H. V. Sutherland, JRS 51 (1961), 94-97.
That is why I mentioned that this coin likely did not circulate long after the defeat of Licinius. Even in the territory of Licinius these coins seemed to have not been well received because of the reduction in value; which may have been reason enough for someone to scratch the obverse. I imagine after his defeat, all Licinius coinage was quickly removed from circulation, though sometimes you find these IOVI types overstruck with Constantinian types, like campgates. This was done unofficially, and probably as a stopgap until sufficient good money could make it into Constantine's newly acquired territories.