We well can know that the 42 mos. or Re 13: are literal time as we know the prophecy of that Chapter started in 1798. It is only 46 yrs. and it is 1844, the end of time reckoned for a yr.
The last 42 mos. the beast is to continue begins when the deadly wound is healed. The problem with setting a time to start it is, who can determine when it is a sure thing that Martyrdom has began with His True Saints again without recompense.