Complex sentence: The database is refreshed every night with updates of the day's Presto fare purchases when the buses return to the garages; this requires users to wait up to 24 hours before cash loaded onto their card accounts is recognized by the readers.
Split into simpler sentences: The database is refreshed every night when the buses return to the garages. This explains why users must wait up to 24 hours before cash loaded onto their card accounts is recognized by the readers.