I'm not sure about the cost of running a reserve grade but I can't imagine picking up an additional 10-15 will be particularly cheap, perhaps on a pay as you play basis for the bare minimum. Hopefully it doesn't have too much of an affect on the NCL or the wider amateur game as a whole, I do on the whole see the return of the Reserve grade as a positive.
https://www.superleague.co.uk/article/913/reserve-grade-to-return-in-2020 Will be interesting to see the SL clubs raid all the top young players from the NCL. Perhaps i'll be wrong, and it could open the conversation again surrounding dual-reg in the NCL. Interesting times...