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Perform Direct Analysis for Serviceability and Strength design in one Staad file

My question has two parts .

1. When using the command PERFORM DIRECT ANALYSIS is the stiffness of the structural member reduced or does REDUCEEI 1 need to be explicitly mentioned?

2. How can I perform the staad analysis for serviceability design following strength design since stiffness should not be reduced using PERFORM DIRECT ANALYSIS LRFD PDITER 15 REDUCEDEI 1 TBITER?

Please let me know if the following example is correct. If yes, is a CHANGE command required following the PERFORM DIRECT ANALYSIS .. command?

STAAD SPACE
...
LOAD 1  (DS1)  * DEADLOAD_OF_STRUCTURE-SELFWEIGHT
SELFWEIGHT Y -1
MEMBER LOAD
1 CON GY 0 0
...
LOAD 60 (ECZ)  * NONSTRUCTURAL_COMPONENTS_EARTHQUAKE_LOAD_+Z
MEMBER LOAD
1 CON GY 0 0
*
PERFORM ANALYSIS
CHANGE
*
LOAD 101 *---------|Frame| P1F: 0.9 (Ds + De) + 1.2 Ts + 1.0 W-------*  L-101
REPEAT LOAD
1 0.9 2 0.9 3 0.9 4 0.9 5 0.9 6 0.9 7 0.9 8 0.9 52 1.2 53 1 54 1 -
55 1 56 1
NOTIONAL LOAD
1 X 0.0018 2 X 0.0018 3 X 0.0018 4 X 0.0018 5 X 0.0018 6 X 0.0018 -
7 X 0.0018 8 X 0.0018 1 Z 0.0018 2 Z 0.0018 3 Z 0.0018 4 Z 0.0018 -
5 Z 0.0018 6 Z 0.0018 7 Z 0.0018 8 Z 0.0018
*
PERFORM DIRECT ANALYSIS LRFD PDITER 15 REDUCEDEI 1 TBITER
*
LOAD 201 *---------|Frame| P1F: 0.9 (Ds + De) + 1.2 Ts + 1.0 W-------*  L-101
REPEAT LOAD
1 0.9 2 0.9 3 0.9 4 0.9 5 0.9 6 0.9 7 0.9 8 0.9 52 1.2 53 1 54 1 -
55 1 56 1
NOTIONAL LOAD
1 X 0.0018 2 X 0.0018 3 X 0.0018 4 X 0.0018 5 X 0.0018 6 X 0.0018 -
7 X 0.0018 8 X 0.0018 1 Z 0.0018 2 Z 0.0018 3 Z 0.0018 4 Z 0.0018 -
5 Z 0.0018 6 Z 0.0018 7 Z 0.0018 8 Z 0.0018
*
PERFORM PDELTA 15
...
**++++++++++++++++++++++++++++++ DESIGN CHECK +++++++++++++++++++++++++++++**
...
*(LY/LZ)
...
LOAD LIST 101
PARAMETER 1
CODE AISC UNIFIED 2010
CHECK CODE MEMB _STL-ALL
*
LOAD LIST 201
PARAMETER 2
CODE BRITISH
TRACK 4 MEMB_STL-COLUMN
DFF ALL
DJ1 1 MEMB 16
DJ2 2 MEMB 16
CAN 1.0 ALL
CHECK CODE MEMB _STL-COLUMN
*
UNIT INCHES KIP
STEEL TAKE OFF ALL
FINISH