21 year old will age out into the longer category.
18 year old well should be good unless there is major retrogression as her PD will come up before she is 21, and CSPA will no doubt give her a few extra months.
Those PD's are a guide, just need to check on them periodically to see how their cases are progressing.
My best guess is that the two younger ones are probably looking at late 2017, the older one 2023 or a bit later.
