Can i upload FW with SP-Flash-Tool without loosing data?

Hello experts.

If i upload latest firmware, all my data on the watch is lost. can i prevent that?
Thanks for advice and it´s ok to rant if it´s already posted somewhere…

Thank you.

Don’t flash userdata.img and cache.img and data on your watch should be left intact (there is slight possibility that some apps might behave oddly in that case clear data of that app).