Loading one document, index fields on first page, how to stop scanning

[PasiPK]

Hello,
I am loading just one long line data document.
It has ASA/CC characters in first column, so there are multiple pages.
All pages have exactly same titles, from which index fields are picked.
So the needed index values are found already on first page,
and all the following pages have the same values.

I have
TRIGGER1=*,1,X'F1',(TYPE=GROUP)  /* 1 */
FIELD1=1,9,10,(TRIGGER=1,BASE=0)
etc.
INDEX1='KEY1',FIELD1,(TYPE=GROUP,BREAK=YES)
etc.
all INDEXn have TYPE=GROUP,BREAK=YES.

My understanding is, that all pages are scanned.
Which in this application is wasted work, because values do not change.
Probably not a big deal, but would there be some better way to do this?

Pasi