let dateTimeFrameOptions = [
	{ "dateTimeFrame" : "90", "desc" : "Rolling 3 Months", "startDate" : "", "endDate" : "" },
	{ "dateTimeFrame" : "180", "desc" : "Rolling 3 Months", "startDate" : "", "endDate" : "" },
	{ "dateTimeFrame" : "270", "desc" : "Rolling 3 Months", "startDate" : "", "endDate" : "" },
	{ "dateTimeFrame" : "360", "desc" : "Rolling 3 Months", "startDate" : "", "endDate" : "" },
	{ "dateTimeFrame" : "TT", "desc" : "This Trimester", "startDate" : "", "endDate" : "" },
	{ "dateTimeFrame" : "LT", "desc" : "Last Trimester", "startDate" : "", "endDate" : "" },
];

let today = new Date().toLocaleDateString();

for( let i = 0; i < dateTimeFrameOptions.length; i++ ) {
	var rolledBackToDate = new Date();
	
	if( $.isNumeric( dateTimeFrameOptions[i].dateTimeFrame ) ) {
	rolledBackToDate.setDate( rolledBackToDate.getDate() - dateTimeFrameOptions[i].dateTimeFrame );
	dateTimeFrameOptions[i].startDate = rolledBackToDate.toLocaleDateString();
	dateTimeFrameOptions[i].endDate = today;
	} else {
		alert( dateTimeFrameOptions[i].dateTimeFrame );
	}
}

console.log( dateTimeFrameOptions );