It could be that the Dreamliner is back in the air in a couple of weeks however surely the 50 aircraft already delivered to airlines would become a priority to getting back in the air.
Then you surely would have to take into consideration how far down the line are the Thomson deliveries in the backlog as I believe they have to complete test flights before delivery.
Then you have to take into consideration that training flights would also take place initially with no passengers on board before they can then introduce them on the shorthaul routes as they initially desired before introducing them on to the longer sectors.
Assuming the plans of introduction into service by Thomson remain the same then one could only imagine that you would have to wait for first delivery to the airline before you can truly estimate when the first revenue flight will actually operate.