Arcana Coelestia #486
486. Verse 4 And the days of Man after he beget Seth were eight hundred years; and he beget sons and daughters.
'Days' means periods of time and states in general. 'Years' means periods of time and states in particular. 'Sons and daughters' means the truths and goods that they perceived.
Arcana Coelestia #7986
7986. 'And so it was at the end of the four hundred and thirty years' means the time of the Lord's Coming, when they were saved. This is clear from the meaning of 'the four hundred and thirty years' as a state made complete and the duration of the vastation or molestation of those belonging to the spiritual Church who were held back on the lower earth until the Lord's Coming, when they were delivered, dealt with immediately above in 7985, and in 6854, 6914, 7035, 7091, 7828, 7932. So it is that 'at the end of those years' means the time of the Lord's Coming, when they were saved.