"After that I will be able to sit back and realise what has just happened."
Hartley will definitely see out the remaining two rounds this year with the Toro Rosso in Formula 1 and has been tipped for the fulltime seat next season but he remains contracted to Porsche at the same time.
Porsche will withdraw from the WEC at the end of this season but are rumoured to be interested in a move into Formula 1 in the future. Hartley gaining experience over the next 18 months in the sport's premier category could be a good thing for Porsche longer term.
Hartley wouldn't confirm whether that were the case but he admitted to hoping to be contracted to both Toro Rosso and Porsche in 2018.
"I would love that but at the moment I don't really know a hundred percent how it is all going to work," he said. "There is still a bit to figure out.
"I have the opportunity to stay with Porsche," he added.
"Basically with all the drivers at Porsche we had the opportunity to stay on and potentially mix up the program. That is something I am unsure of at the moment - how that would work.
"I obviously have a great relationship with them and would like to keep that going. They are the ones that gave me the huge break four years ago to enter LMP1.
"I think it was the best possible preparation I could have had to get to Formula 1."
If things go to plan overnight he will at least finish his time in WEC on a high.
"It isn't done yet," he said. "We are pretty close but anyone that has followed endurance racing for the past couple of years will know that anything can happen. There are so many variables and they are tough races so we are not getting ahead of ourselves."