Generally speaking, that is not true. If your dates fall during President's Week, that's a high occupancy period, but in general, March is much busier than February.
Keep trying....
We were booked through National Emerald aisle. I had made the ressie in Dec. because I could not get a good rate at Dollar. I booked a full size hoping that a mini-van would be on the aisle. Just last I week I tried Dollar with a code I found here and I got the mini-van for 209.00 per week then a daily rate of I think it was 39.99 for 2 extra days. ( I am going for 9 days.) We are arriving on the 14th but staying until the 23rd, which is most of Presidents week.