Incidentally, such simultaneous cancellation and rebooking of forward contracts for rollover is exempted from the RBI restrictions introduced on 15th December, 2011. Of course, precisely the same strategy can be replicated in the exchange-traded foreign currency futures markets as well. Contrary to the popular perception, this strategy is fairly simple and perfectly do-able and locks in the original starting spot exchange rate.
What, in other words, this entirely unexceptionable, and highly desirable, strategy does is substitute volatility of the spot exchange rate with that of forward margins at each roll over date. It is empirically, and  2  BIS central bankers’ speeches  anecdotally, established that volatility of forward margins is far less onerous than that of the spot exchange rate.