I haven't read/heard anything related to a reboot after the next installment. Isn't Sam signed on through 5, and possibly 6? I'd be surprised if he would be a part of that if it happens, and the more I think about it, a reboot will possibly only happen if Marvel gets a hold of the rights. I don't have any idea what the likelihood of that is.
And I'd be shocked if Gwen wasn't murdered by the GG if the reboot does so happen. It's so epically defining and nonetheless, pretty moving stuff.