Before you use BigPicture Power-Up for the first time it's good to know that...
A card in Trello is not like a task in BigPicture.
The former has only a Due date field that indicates when a card starts being "due" and this can be considered as a card's planned end date. Though, it does not have any field brought by Trello nor any custom field that may store information about a start date of a card.
On the other hand, BigPicture requires a card to have both – a start date and end date – in order to visualize it on the Gantt chart. Whilst pulling a card into the Gantt, BigPicture gets its Due date and maps it to BigPicture's End Date field. As BigPicture also needs to pick a date to map it to Start Date field, a card's date of creation becomes task's Start Date. This way a Trello card can be displayed on a Gantt's grid. However, here comes the tricky part.
If a user sets Due date to the past and a card's date of creation is later than a Due date then such a card becomes a task with duration of a one day after being pulled into the Gantt. Why is that? BigPicture seeks for the afore-mentioned dates and faces a situation when Start Date is later than End Date what, in terms of displaying tasks in the Gantt, is clearly wrong. To overcome this, the Power-Up makes a correction of dates and changes a task's End Date to Start Date just to meet a basic logic condition – Start Date cannot be later than End Date. As a consequence of End Date's change, a Trello card's Due Date also changes.
For some Trello users such a change may have a huge impact on what they have worked on prior to. Please, note it!
BigPicture for Trello is a PPM Power-Up tool which enhances the project management experience to those users who like to plan with Trello. The early release is limited to a Gantt chart with WBS though it will introduce more and more features initially present in its Jira release including the SAFe Roadmaps and Boards, Risks module or Resources and Teams management system.
It displays Trello Cards in a form of Tasks which can be easily allocated on the Gantt chart accompanied by the WBS (Work Breakdown Structure) panel. Since Cards are allocated to Boards, we could take an approach in which a Board represents a certain project. Our Power-Up is capable of displaying a number of Cards from multiple Boards (projects) in form of Tasks on the Gantt chart.