This was an option in 2016 where you could cease development towards the end of the current season and gain double resources to spend at the start of the next season. In 2016 it became available after Singapore i if i remember correctly. Im currently at COTA now and cant see it anywhere.
Well ofcourse you could.... But the idea is that in 2016 you opt to cease R & D and gain double resources for the start of the next season. Not spending the resources is pointless.
In 2017 you can't once you've started the R & D but on a positive note, the unfinished R & D carries over (if you stay with the same team) to the next season and you get awarded bonus points (I got over 2,000) to kick off the new season. That's pretty good! Now, if only they could fix the SC issue to unbreak the game...