When a host system requests updates, it must factor in the flash update times associated with the gauges firmware. The gauge firmware ACKs a properly received data flash write request. This has the effect to immediately release the bus. The bus will be released when the gauge firmware has properly received data flash write request(ACK). The bus will be released before the end of the flash write so the host should delay 250 ms after receiving an ACK to ensure all actions have been completed. In regards to MAC commands the host should allot 2 ms for the gauge to prepare the data. For commands that request the gauge to compute checksums it is recommended that 20 ms should be allotted.
More timing Considerations can be found in Chapter 8 of the TRM.