Question about Initial Treatment with Zytiga

My brother-in-law was recently diagnosed with GL8 prostate cancer (PSA 24) that is not systemic as demonstrated from a recent psma-PET scan. His MRI indicates, though, some activity outside the gland.

So after his first meeting with an Oncologist, the treatment plan suggested was IMRT (40 sessions 79-81Gy) with hormone treatments for two years. His doctor suggested Lupron AND Zytiga during that time. Is this the newest treatment for initial treatment of prostate cancer using both these drugs together? Is there not advantage to saving second line hormone treatments (Xtandi, Zytiga, etc.) for later treatment options in case of recurrence?

Really appreciate your comments.

DougS