Max, this solution may suit your needs?
Create a survey page at the very front of your survey that is used to store the below Perl Script. Insert this Perl Script in to the footer of this survey page.
[%Begin Unverified Perl
use POSIX qw(strftime);
my $DayOfWeekID="";
$DayOfWeekID=strftime "%w", localtime;
SETVALUE("DayID",$DayOfWeekID);
End Unverified%]
This page is not displayed to the respondent. It simply runs the Perl Script. This survey page can be a select question without question script using a constructed list that evaluates to one item. That will certainly work and will never be displayed to the respondent. You can also use a free format hidden question as an alternative.
Now create a pass-in field called "DayID" and define it as a whole number.
So "DayID" saves the day of the week as an integer with Sunday=0, Monday=1, Tuesday=2, Wednesday=3, Thursday=4, Friday=5 and Saturday=6.
For every password you import, you can allocate a day of the week that uses the same 0-6 definitions. Assume this is called "SampleDay".
Now you can compare "DayID" (the actual day) with "SampleDay" (the sample day) in skip logic to control the respondents movement.
e.g.
If DayID=SampleDay, skip to Q1.