1000 from Penzance is a
FGW▸ HST▸ , arrive Taunton at 1334. Then 1411 from Taunton direct to Newport arrive 1606, should be a Class 158, thus neatly avoiding a Vomiter and another change at Bristol. Or take the 1354 Vomiter from Taunton and change at Bristol for the 1448 to Newport arriving 1527.
The 1000 from Penzance has a Restaurant from Plymouth at 1200, maybe enough time to sample the Pullman lunch offering; ask nicely to be served first and you may get two courses in before Taunton!
As it's a BH Monday you can upgrade to Weekend First on the leg from Penzance to Taunton, that's if you're not on a 1st Class ticket already!
EDIT: Thought just occured to me. As it's a BH Monday the Pullman restaurant may not be running....will still be a HST though!
2nd EDIT (
) The 1354
XC▸ Vomiter from Taunton is routed tomorrow via South Wales arriving Newport at 1508. Engineering I guess.....