There's a few possible explanations for why the first week may be like that. CBS perhaps wants to see if its compatible with Survivor on Wednesdays to see how it does to maybe mix up the schedule for next year. Or maybe they are unhappy with the Friday ratings and are hoping that extra exposure on Wednesday will be enough to gain more eyeballs to follow the show to Fridays.
As for the scheduling, being a huge college basketball fan, CBS is always pre-empted on the final 2 Fridays in March for the round of 64, and the Sweet 16. With episode 2 on Friday Feb 27, that would put all 1 hour episodes with a finale on Friday May 22 (my birthday!), but as theschnauzers mentioned, that is unlikely as it is out of sweeps. I would wager on a 2 hour finale on May 15 (or a random 2 hour episode in the middle of the season while still ending on the 15th).