This article is interesting for two reasons:
It reveals that there will be a significant delay in completing the church, beyond the most recently planned date of 2026. The reason is the huge drop-off in visitor revenue--the primary source of construction funds--due to the pandemic.
It indicates that when the building reopens for visitors on May 29, it will (initially) be only on weekend mornings. There is no explanation given for that limited access period. Perhaps it's related to some weekday construction work that has been going on during the closure that takes time to bring to a close? This is obviously not good for tourists with hopes of seeing the church in the near future.
Perhaps more information is available in the Spanish/Catalunyan press.