Complex sentence: The Block 3i software was intended to be a rehosting of the Block 2B software on the updated Integrated Core Processor, but this has caused a timing misalignment that has reduced stability, requiring reboots in flight.
Split into simpler sentences: The Block 3I software was intended to be a revision of the Block 2B software to run on the updated Integrated Core Processor,. Unfortunately, it resulted in a timing misalignment that reduced stability, requiring reboots in flight.