trigger ForARPU on Case (after insert,after update,after delete)
{
Id recordTypeId = [Select Id From RecordType Where DeveloperName = 'Customer_Order'].Id;
List<Case> CaseIDs = new List<Case>();
for (Case s : Trigger.new)
{
    if(s.RecordTypeId == recordTypeId )
    {
        if(s.Case_Details__c ='New Subscription' || s.Case_Details__c ='Add On')
        {
        CaseIDs.add(s);
        }
    }
}
}

Boolean isNewSubscription = s.Case_Details == 'New Subscription';