Automate applying due date set on a Trello card to the attached card on another board

[Alan Burnce]

I am trying to do this through automation but I cannot figure it out. I've referenced this article.

I have used automation to create a new card on an overview board every time I add a card to one of several project boards. That's working fine. But I then want to be able to set due dates on these cards in the project board and have that date automatically added to the linked card on the overview board. I don't want to use a full mirroring solution like Unito because I'm a solo freelancer and don't need to pay for something that robust and designed for teams. From what it seems, I should be able to do this, just in one direction (overview board would never be directly altered). But I can't figure out how.

Help? TIA. 

[Mike - Dreamsuite Consulting]

First of all, you should...

When a card is added to the board, , copy the card to the overview board and link the cards together

Second, this is a bit rubbish but you can't port the due date directly to the linked card directly.  The best option is to use a date custom field, I'll call it date_mirror for this example.

Set an automation,

when a due date is set on a card, find the first card linked in the attachments and set custom field "date_mirror" to {triggercardduedate}

Lastly, create an automation on the overview board,

when the custom field date_mirror is set, set the due date to {customfieldvalue}