You want to know if the WebSphere MQ AMQAJRN Receiver size options attribute can be set to *MAXOPT3?
WebSphere MQ Support does not recommend setting the Receiver Size options attribute to a value of *MAXOPT3. The current default setting is *MAXOPT2, which will cause the journal sequence number to be reset to a value of 1 after an IPL of the system. *MAXOPT3 is not recommended, since the product does not support sequence numbers greater than 9 999 999 999.
Excerpt from IBM i Information Center:
IBM i 7.1 Information Center > Systems management > Journal management > Local journal management > Managing journals > Swapping, deleting, and saving journals and receivers
"If you use system journal-receiver management for a journal and RCVSIZOPT(*MAXOPT3) is not specified, the sequence number for the journal is reset to 1 whenever you restart the system or vary on the independent disk pool containing the journal. When you restart the system or vary on an independent disk pool, the system performs the change journal operation for every journal on the system or disk pool that specifies system journal-receiver management. The operation that the system performs is equivalent to CHGJRN JRN(xxx) JRNRCV(*GEN) SEQOPT(*RESET). "
If you specify RCVSIZOPT(*MAXOPT1), RCVSIZOPT(*MAXOPT2), or RCVSIZOPT(*SYSDFT) for the journal to which you attached the receiver, the maximum sequence number is 9 999 999 999.
If you specify RCVSIZOPT(*MAXOPT3), the maximum sequence number is 18 446 744 073 709 551 600.