The other rumour was Will Homer from Jersey (previously of LI and Bath, brother of Tom)
Porter is definitely ready to step up, problem is we need 4 SHs to cover all competitions, especially if Robson has injury concerns or is away with England.
There is not a younger academy product coming through below Porter as yet and with Vellacott still quite inexperienced it could be a great battle having Porter, Vellacott and Homer fighting it out and being rotated across all of the competitions for second choice.
Porter is definitely highly regarded as has been given the captaincy in the AWC despite being younger than most at the time. Homer is arguably more experienced than Porter, so it could be an exciting time for young scrum halves at wasps (if Homer signs)
If they all stay fit however Dai has a job on his hands (as in other key positions) at keeping everyone happy and on a steady development path with the amount of gametime they get.