regarding bltlength of same spec and same dia of blt and different number of bolts

Nothing required in Paragon.
Did you set the BLTREF for XXX to the new SBOL in the Bolt spec

$S-
$(  BORE UNITS MM    $)
$(  DISTANCE UNITS MM    $)

NEW SPECIFICATION /BPWMSCC
VERSION 1151
MATREF =0
FLUREF =0
RATING 0.000
LINETYPE NULL
BSPEC =0

TEXT 'BOLTING'

HEADING
TYPE  NAME          BDIA   BTYP  BSEL  SHOP  CATREF  DETAIL                                        MATXT                     CMPREF  BLTREF
DEFAULTS                                                                                          
-     -             -      BOLT  DEF   =                                                          
BOLT  */BBWMSCCD      12.70  BOLT  DEF   FALS  /BOLT   /STUDBOLT.+.2.HVY.HEX.NUTS.ASME.B1.1/B18.2.2  /ASTM.A320.GrL7/A194.Gr4  =0      /BBWMSCCD
BOLT  */BBWMSCCD:X  12.70  BOLT  XXX   FALS  /BOLT   /STUDBOLT.+.2.HVY.HEX.NUTS.ASME.B1.1/B18.2.2  /ASTM.A320.GrL7/A194.Gr4  =0      /BBWMXCCD


I use this method to switch bolts for Insulation Gaskets so there is no reason I can think of that it should not work in your situation