Tamoxifen before or after radiotherapy?

My Onc put me on Tami about 4 weeks after surgery.

About 2 weeks now till radiotherapy.

Just Googling and read debate about before or after rads.

Increased fibrosis if on Tami during rads?  Wonder if that’s true?

I was given choice re rads and accepted as unsure how long I’ll stick Tami.

Now unsure about doing rads!