Premium Gateway Credentials

Over the past couple of years, we've intermittently had reloads fail due to the pbix using one SQL service account and the gateway using another.  Meaning, the same account had to be used across the board.  Updates were made.

Tested this morning and found that the same SA no longer required.  Used two different SA's, remapped them, and it loaded fine.  Even used my windows account in the pbix and was able to map to the gateway SQL SA connection (in the service).

It might have been like this for awhile or since inception.  But does anyone know if it should be like it is now?  I want to clean up our connections but need to know this before starting.