How Maintenance plan with Counter create order only depend on Counter document

The business scenario : Equipment running 168 hours create the maintenance order from counter plan.

Business data:

1. ik01: AnnualEstimate:7200Hours CntrOverReadg:999999999Hours

2. ik01: create a task list for this plan

3. ip41: create a plan with counter ;Cycle/Unit:168 Hours ;Call horizon:100%;SchedPeriod:999day

4. ik11: Set the initial value: 7777

5. IP30: Set background job : every 12hours update this counter plan

Questions:

1. When I use Tcode:Ik11 set the Counter document,the totally Difference vaule not reach the 168H.The order was created.

Why is the order was created ahead of time? (As shown in attached pictures)

2. If the Equipment turn off in past two days, What value need to input Counter document(IK11)

As the same vaule with the last reading input?

3. How can I make the counter plan create order only depend on input Counter document?