The Time of Christ's Return

The all-history timescale foretold in the Book of Enoch means a second coming of the Christ by 2050 AD at latest and most likely before 2040:

Creation of Adam c3950-40 BC
Flood c2550-40 BC
Abraham c1850-40 BC
Law c1150-40 BC
Second Temple c460-40 BC (reference point for these BC/AD dates)
Ascension between 460 BC and 250 AD
The Final Judgement before 3050

Source: Book of Enoch chapters 90-91