If you need additional time to qualify for the bonafide residence foreign earned income exclusion (form 2555) you can file form 2350 to extend your return further out until a date you have qualified for a full calendar year living abroad.
Your Form 114 (FBAR) which reports your foreign financial accounts is due on 6/30/15 for 2014 and cannot be extended any further. Failure to timely file this reporting form can result in substantial penalties. You can only file this form on line at http://bsaefiling.fincen.treas.gov/NoRegFBARFiler.html
Though expats get these special extension rules, any taxes owed must be paid in by 4/15/15 to avoid penalty and interest charges if any taxes are later due with the return.