Between the last La Liga game and the Champions League returning there will be a 19 day gap. That is where Barca's preparations for the tournament will take place. The new format could favour Barca, who just have to win three games to get to the final on August 23. These 19 days could be decisive to refresh the team and get ready for the Napoli clash on August 8.
Quique Setien and his technical team are interested in having a couple of friendlies against Catalan sides in the gap to make sure the team is match fit. However, that might not be possible depending on the virus, with Lleida back in lockdown and other places potentially following. If that's how it goes, they'll play some internal friendlies - against the B team for example, or inter-squad.
Setien will give at least five days of rest to the team after La Liga ends. They will have a week off basically, 20 to 26 in total disconnection. If the league is over on Thursday then some players may be given extra time, starting before that too.
From July 27 Barcelona will be back and preparing totally for the Champions League.
If they beat Napoli in the last 16 they face Bayern Munich (or Chelsea, but come on), and then in the semis will be Real Madrid, Man City, Juve or Olympique Lyon.
Antoine Griezmann is hoping to return in this period, along with long-term absentee Ousmane Dembele.