parse string - default values

We have an automation that has an email as the trigger.
In this email there is a string in this format:

taak:J:01/12/2023:31/12/2023:4u:description

With this I want to create a task in motion.
I can split the string so I have the separate array values.
action: taak
person: J
start date: 1/12/2023
due date: 31/12/2023
duration: 4u
Description: description

But, how can I easily add a default value if the sent string is for example:

taak:J::31/12/2023:4u:description (there is no start date). I would like to put in a default value (for example today).
Same goes for all the other ones.

Filters are not appropriate because it needs to continue, regardless. Router is not working here either.
Do I need to write a regex expression?

Is there an easy way to do this?

Hey @GroeiGarage

Kindly provide us the workflow name in which you are getting issue.

So we can check on it and guide you further.

It is not an issue, it is something I want to do.

Please allow me some time to check your use case with our team. I will get back to you soon.

Filters are not appropriate because it needs to continue, regardless. Router is not working here either.
Do I need to write a regex expression?