Forecast Consumption and plan options

Why forecast consumption happened beyond the Foreward days 91 (plan option foreward days 91)

I have forecast on 6th June 2016 around 15780 Quantity. It consumed part of FCST and shows remaining as over consumption (7488 Quantity).

1) Is this implies that, forecast values are under the actual demand?

2) What calendar will be considered while forecast consumption.

Here with attached the FCST, SO, Consumption and Plan Options.

   

START_TIME	QUANTITY	CREATION_DATE	Fiscal Quarter	Remarks
2/1/2016	4	04/09/16	2016-4	Consumed as per expectation
2/10/2016	4	04/09/16	2016-4
2/15/2016	4	04/09/16	2016-4
2/22/2016	4	04/09/16	2016-4
2/29/2016	4	04/09/16	2016-4
3/7/2016	4	04/09/16	2016-4
3/14/2016	4	04/09/16	2016-4
3/21/2016	4	04/09/16	2016-4
3/28/2016	4	04/09/16	2016-4
4/4/2016	4	04/09/16	2016-4
4/11/2016	4	04/09/16	2016-4
4/18/2016	3	04/09/16	2016-4
4/25/2016	3	04/09/16	2016-4
5/2/2016	135	04/09/16	2017-1	Sales Order Qty#15780 placed on 6th June 2016. It backward consumed 5 weeks (and it is with in 90 days, and we do not have quantity to consume backward).