@Gleno0h I have done it via a shell device but is it possible without?( only with a rule and a variable) only to handle it with minimal effort (and for my interest). As a hint: I have a shell device with the system date which display by %d-%m-%Y, is it possible to set a variable by rule with some regular expressions?
I think sth about
.... Set $variable to execute "echo date +\"%m\" "
Some more background I want tfor my energy and gas calculation define the day/month/year change and execute the calculation at 0:00 directly