Setting layout to a report in background job

Hi.

Does anybody knows how I set layouts dynamically to a report output, given that such report is scheduled to run once a day in a background job?

It would work for me, either: through SM36 or coding JOB_OPEN / JOB_SUBMIT / JOB_CLOSE (or any other option, if available).

My requirement is to execute every night few reports, each with their corresponding variants and layouts.

Something like:

RUN <report1> VARIANT <variant1> LAYOUT <layout1> JOB <job>. (it would output and xls file).

RUN <report2> VARIANT <variant2> LAYOUT <layout1> JOB <job>. (it would output another xls file).

RUN <report3> VARIANT <variant3> LAYOUT <layout2> JOB <job>. (it would output a 3rd xls file).

How should I do to inform variant and layout parameters?

Thank you.

Rafael.