I’m just reporting what my friend told me. Bought the standard physical PS4 copy, got the PS4 DDE shortly on sale and had to restart progress on the same console. One thing to note is that standard copies have a white “BATTLEBORN” title at the main menu, and DDEs have the title in gold with “Digital Deluxe Edition” below it.
Images grabbed from Google, not my own:
They seem to be treated as separate. I just wanted you to be aware that this may a possibility if you wanted to make the transistion. The three legendary packs help out a tiny bit however, got the Generous Refund Policy shard generator right off the bat when I rebought the DDE on Xbox. (Wanted that forever on PS4 and could never get it, first one I pulled on Xbox, lol.)
Luckily my friend only just started and didn’t lose much. Even starting again on a different console was hard for me after mastering quite a few of my favourites, but that just means I can surprise higher ranked players when I melt them in PvP, lol. Gonna miss my full bank pages of legendaries, though.