Such songs were written and rewritten time and time again by the broadside hacks rearranging lines here and there and including contemporary ship names, anything that would enhance their saleability.
This particular ballad above is very much of that type. Stanzas 2, 3, 6 and 7 at least can be found in many similar ballads. Someone has already mentioned The Royal Oak family of ballads. As for the date I have just been looking at and comparing 8 versions of a similar ballad and not one of them contains the same date.
If Les is right and the ballad had ancestors going back to the 16th century that's a long period for all sorts of alterations to have taken place. 4 centuries is a long time for a ballad to survive solely in oral tradition so it is very likely there were many different printed versions during the intervening centuries.