Future date enable this year april

HI Selva,

You can try the below updated code:

$(function () {
																					
    var currentDate = new Date();
    var year = currentDate.getFullYear();
    
    // Set April 1st of the current year as the minimum selectable date
    var minimumDate = new Date(year, 3, 1); // Month is 0-indexed, so 3 = April

    $("#<%=txt_installationDate.ClientID %>").datepicker({
        changeMonth: true,
        changeYear: true,
        dateFormat: "dd/M/yy",
        minDate: minimumDate, // Minimum date is April 1st of this year
        maxDate: "+12m", // Allow up to 12 months in the future		 
        showOn: "both",
        buttonImage: "../img/calendar.png",
        buttonImageOnly: true,
        onClose: function (selectedDate) {
            $("#<%=txt_installationDate.ClientID %>").datepicker("option", "minDate", selectedDate);
        }
    });
});

$(function () {
    var minimumdate = new Date(); 
    var futureDate = new Date(minimumdate.getFullYear(), 3, 1);
    
    $("#<%=txt_installationDate.ClientID %>").datepicker({
        changeMonth: true,
        changeYear: true,
        dateFormat: "dd/M/yy",
        minDate: futureDate, 
        maxDate: "+12m", 
        showOn: "button",
        showOn: "both",
        buttonImage: "../img/calendar.png",
        buttonImageOnly: true,
        onClose: function (selectedDate) {
            $("#<%=txt_installationDate.ClientID %>").datepicker("option", "minDate", selectedDate);
        }
    });
});

Try to set minDate to the desired future date in your case 1st April 2025 and set maxDate to allow selection of dates beyond April 2025 if you need it :