IMHO the kids already suspect something is going on. They are more intuitive than you would think, even at a young age.
As far as timing in when to tell them. The time is never going to be 'right'. But they do need to time absorb it all before a significant change is made.
In my sitch, we announced the separation to the kids when evidence of the move became apparent such as the packing up of boxes. The timing was about 2 weeks prior to H moving out.
Me & H: 33 yrs S: 4 & 6 D: 2 M: 9 yrs ILYBNILWY: 8/09 SEPARATED: 9/09 The Beginning
