Caserio said last night that they'll put everyone out on the field and then put the best 5 together.
If we trade Mason (or any other o-lineman) it will likely be during training camp or at cut down time. Doing it now is foolish. An injury or two and we would need all of them.
They will probably go into the year with 8-9 lineman, 4 of which are tackles, which is fairly standard. At the minute that looks like:
OT: Waddle, Cannon, Brown, Garcia
G/C: Wynn (possible tackle too), Andrews, Mason, Thuney, Croston
That is a pretty solid group and would leave the likes of Jelks, Tobin, Ferentz on the outside looking in. You do wonder why they felt they needed Brown though - he is a definitive RT. Do they think he can play on the left? Or is there an issue with Cannon? Maybe they have no confidence in Garcia for this year. Who knows....