Hi,
for SCTN you can modify position of START and END point. When you like to use command line then:
- first of options is set new position of START od END point. Q POSS POSE return position of START and END of SCTN, then command POSS E123mm N456mm U0mm modify position of start. Similar for end.
- other option is use command EXTEND. To move start point you can use example: EXTEND START 250mm or to move END point EXTEND 300mm
There are several ways indeed, but the point is EXTEND does not function as pml command anymore. So to extend the start or end now the direction and position of the start or end must be known and then move start or end to new calculated position. So not as easy as it was.
Of course as Corrado said you use grips and drag, usefull of course for one SCTN or GENSEC.