Hi ​@NormanThink ,

In the Maintenance Center → System changes select tab Applied changes. On each line, or grouped by date, you can find the changes that you have applied on your Dev environment. Via the 3 vertical dots on the right you can export the changes in json files (for each change one file). 

In the higher environment also open  Maintenance Center → System changes but now select tab Pending changes. If you click Add change a windows open in which you can drag one json file at a time, starting with the first change.

Like this you simply replay everything you did in the Dev environment. Downside of this approach is that if you have come to the end result with much of experimenting, applying corrections etc, you replay that as well. For easier changes it might be better then to just rebuild the solution in the higher environment.

Kind regards,

Albert