From the TYPE=HISTORY Parameters, it appears that the OLIMIT maximum is 9999
How to select all records in a batch TYPE=HISTORY request?
Increasing OLIMIT would be classified as an enhancement request. An Idea requesting it can be created on the Ideas Community using Category "XCOM Data Transport" and then XCOM Product Management will assess it.
Workarounds:
1. Run XCOMEHRP directly against the XCOMHIST VSAM data set.
2. Use an IDCAMS REPRO, or SORT execution to make a flat file copy of the XCOMHIST data set for subsequent reporting based on the HSTDSECT layout. Using SORT to create the copy of history records offers the added benefit of record and field level selection of data from the VSAM history file.
3. Limit the start/end date and time values (OSDATE, OEDATE, OSTIME, OETIME) so the 9999 limit for records returned is never exceeded for each XCOMJOBH job run and then run multiple jobs to cover the whole date/time range required.