In the year 20,099 the Christian and Islamic calendars will synchronize. Right now the Islamic calendar count is 679 years 'behind' the Western-Christian year of 2015. It is the year 1436 Islamic Time, but 2015 by standard Christian Time.
Thus the years in between 20099AD until 20031HE will match up. Also note, the Islamic Calendar will eventually surpass and run faster than the Christian calendar by one year. Thus the year 20032AH will match to the year 20031AD.