Multiple criteria timestamp - google-sheets

Question

I am using...
function onEdit() {
var s = SpreadsheetApp.getActiveSheet();
var r = s.getActiveCell();
var time = new Date(+new Date + (1000 * 60 * 60 * 24 * 7));
time = Utilities.formatDate(time, "GMT-08:00", "MM/dd/yyyy");
if( r.getColumn() == 2 ) { //checks the column
var nextCell = r.offset(0, 6);
if( nextCell.getValue() === '' ) //is empty?
nextCell.setValue(time);
}
}
...to add a timestamp+7 days to column H.
In addition to this timestamp feature... (could be another script)
When column D value = "Questions/Waiting for Info" and then changes to anything else.
and
When column E value = "Preliminary, Less than 25kW" or "Preliminary, Less than 25kW" and then changes to anything except for "Preliminary, Less than 25kW" or "Preliminary, Less than 25kW".
we want to start the timestamp+7 days over again.
It appears that this might not work with onEdit as there are some values that must be read prior to the edit. Not sure how to do this. Thanks
Correct, this is impossible using onEdit without copying the original data somewhere else first. A complicated solution out of my expertise at the moment.

Answer 1

Maybe try something like this
function onEdit(e) {
var d = new Date(new Date() + (1000 * 60 * 60 * 24 * 7));
var time = Utilities.formatDate(d, "GMT-08:00", "MM/dd/yyyy"),
ind = [2, 4].indexOf(e.range.columnStart),
off;
if (ind == 0) {
off = 6;
} else if (ind == 1 && e.value !== "Questions/Waiting for Info") {
off = 4;
}
e.range.offset(0, off).setValue(time)
}