Attend the interview, even if it will result in "decision cannot be made". Once you've done the interview, they have 120 days to decide your case or you'll get to file 1447(b). If you delay the interview by rescheduling, the 120 day clock won't start ticking until later.
If they make the mistake of scheduling you for a same day oath, point out the mistake to them and ask for an oath on or after your 5 year anniversary. You don't want discrepancies like that in your citizenship process to cause problems for you in the future. Even though it's very unlikely for them to revoke your citizenship for having the oath a few days too early, they can hurt you in other ways if they find that your citizenship was improperly obtained, such as not recognizing citizenship for your children or denying your petition to sponsor your spouse.