Just sharing my experience...
Went down to Samsung service center this afternoon due to screen burn in. Got a SMS informing me for collection after 90 mins. Their engineer has replaced new battery, new mid frame and screen for my repair. I found some extra glue stains on my back panel when collecting back my phone. I told the lady CSO to let the engineer assemble again. It took her about 10 mins to return me with a perfect phone (with water resistance passed). It's their SOP to replace these items if there is any screen related issues.
Do note that of there will be additional charges if Samsung CSO finds any crack, dent on the screen, back panel or mid frame. Lastly, the lady CSO told me not to use the phone in high brightness to prevent any burn in on the screen.