Registry system variable @DS = 0 (default).
Set to 1 or any value > 0 will set new project @DSP=1970.
2018 was the only allowed value before for @dsp but there might be instrument data that is prior to 2018. So 1970 should be good enough. There should be no data file that need high time precision before 1970.
When sharing the opju with others with with @ds=0, the project will still keep the higher precision date since project level @dsp is 1970.
It’s also fine to share the 2023b opju with older Origin from 2019 on.