I unhosted the file and it still happens. The problem isn't with the server.
I use the "Set Use System Formats" script step to set the date format to the local date when the file is opened.
Try Set Field [ date ; search Date ] instead.
The suggestion above to use set field will likely work for you. It is always best to avoid manipulating dates by putting them through a "getastext" process, as this does trigger system date options, which as you've discovered, can change arbitrarily. The set field process is "better" also in that it will always work if you are on the correct table; the insert calc result requires that the specified field by on the active layout.
Thanks! In the past (FM11) I had problems scripting date ranges into a date field in find mode using 'set field' because it would complain that the eliipses (...) was not a valid date and using Insert Calculated Result would work around that!
I'm glad that set field is working. And thanks for pointing it out, I shouldn't have assumed that set field would fail.