Super Smash Bros. Ultimate director Masahiro Sakurai has confirmed that Super Smash Bros. Ultimate will be getting a day-one launch update on December 7. The following info is a translation from comments made by Sakurai:
We will distribute our first update on launch day. Players who purchased the digital version don’t need to worry, but players who purchased the physical version should apply this day-one patch before you play. This will also prevent your replays from going off-track. By the way, if you save your replays as videos, you can keep them forever, but note that they take up a lot of space!
Source: Source Gaming