Nein. Es gehen auch mehr.
Ich würde eher darauf tippen, das dein Window in dem die Auflistung erfolgt, zu klein ist.

Ich selber habe auch CHOICE mit > 10 im Einsatz.
PHP-Code:
    A            CHC            2Y 0B  8  9SNGCHCFLD(*RSTCSR *AUTOSLT)      
    
A                                      CHANGE(70)                       
    
A                                      CHCAVAIL((*COLOR BLU))           
    
A                                      DSPATR(HI)                       
    
A                                      CHECK(ER)                        
    
A                                      CHOICE(&TXT1)                  
    
A                                      CHOICE(&TXT2)                  
    
A                                      CHOICE(&TXT3)                  
    
A                                      CHOICE(&TXT4)                  
    
A                                      CHOICE(&TXT5)                  
    
A                                      CHOICE(&TXT6)                  
    
A                                      CHOICE(&TXT7)                  
    
A                                      CHOICE(&TXT8)                  
    
A                                      CHOICE(&TXT9)                  
    
A                                      CHOICE(10 &TXT10)                
    
A                                      CHOICE(11 &TXT11)                
    
A                                      CHOICE(12 &TXT12)                
    
A                                      CHOICE(13 &TXT13)                
    
A                                      CHOICE(14 &TXT14
Läuft ohne Problme
Gruß
Ronald