Domain changes and what happens to the dashboard ?

Hi jolenech,
 
So long as the Heap snippet with the appropriate environment ID is present on the page, data will be captured as expected. Whether or not the definitions will still capture the expected data all depends on the definitions and the Filters that may be used within them for any Domain specifications.
 

For example, if your old Domain was old.prod.website.com and the new Domain was new.website.com, the following definition would not capture pageviews on the new Domain:
Domain equals old.prod.website.com

 
However, the following definition would capture pageviews on the new Domain (as well as historical capture of the old Domain):

Domain contains website.com

 
I hope this helps, but - as always - I'm happy to help answer any questions you may still have.
 
All the best,