Elevator RCOU-C2 & RCOU-C4 constantly actuated up in level cruise flight

Hi, Iam trying to fly a quadplane(baby shark FW250) at lower velocity (20m/s) to reduce power consumption. The objective is to fly it efficiently without any elevator servo actuation (or minimum) during level cruise flight.

I have attached the respective log in which we have faced this issue,

RCOU-C2----->1558
RCOU-C4----->1448

but, TRIM values were set to
SERVO2_TRIM---->1510
SERVO4_TRIM---->1503

we suspected that constant elevator up is because of a forward CG.
As per arduplane documentation if the PIDP.I value was constantly above zero then it can be concluded to be nose heavy or elevator trim error.

First flight
In our first flight we had the CG at forward point and we got PIDP.I ---->5.79
Plane maintains level flight and flies stable.

Second flight
so in the second flight we moved CG behind to the middle point and we got PIDP.I---->2.58
Plane couldn’t maintain level flight, constantly porpoising and had altitude variation.(+/-15m)

I have uploaded both the logs, kindly go through it and give your suggestions…

First flight
Second flight