description change method from stored to deflated, which will change the timestamp because it is at a DST point and not valid in that time zone
environment-set TZ America/New_York
# setting it to a European timezone, where there is no DST change at this point, works
#environment-set TZ Europe/Zurich
return 0
arguments test.zzip  set_file_compression 0 deflate 0
file test.zzip mtime-dstpoint.zip mtime-dstpoint-deflated.zip