Andrew Cashner, who started last night's game for San Diego (and had 9 K's and a QS), is still not eligible to be played in a Starter spot. Obviously this has already cost Cashner owners (however few they may be) innings from any reliever they had to bench to open up a P spot for him, assuming that not all of their Starter spots were taken by active starters. Actually it would be fairly easy to credit said owners with the stats of their best-performing benched reliever for that evening, but that's really just me wishing.
Hey M, I saw you post this question earlier on another post. You can find the original answer to this question posted here, under your reply.
Basically Jay has the right of it. Cashner left last season as a Reliever, and started this season as a Reliever as well. Just this last month, he gained his first two starts, and should be making his 3rd start tonight. This means that he will qualify for SP eligibility after tonight’s start, and should reflect such as of tomorrow, July 4th, barring any changes to who starts tonight's game.
I posted more detail on our fantasy requirements for position eligibility in your original post; check it out for more details on how position eligibility works in our fantasy baseball game.