Hello Kostas,
There is no direct way currently to set pattern like "date("Y-m-d"

" but there are two ways of doing it.
One way is that you can
write your own rule plugin where you can use the date pattern like date("Y-m-d"

and update your custom field.
Second is that In your import file, you have some custom text for date field and you can create a
replacement rule, set this custom text in find field and replace it with the date you want in the replace field in the rule. And of course you need to change the date in the replace field in the rule every time you need to have the current date.
Kind regards,
Tharuna
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