Time between first , second attempt

Hi ,

 I am aware now that PMP will be changing its format and subject after 1st Nov'15. So i got to take the test within this time to stay with the previous format.

 My one year eligibility was till 16th Dec, so now i have to take the test before 1st nov.

 I am planning to take the test end of sep'15, just wanted to check incase i fail in first attemp, can i take the next 2 attempts within a month's time or PMP has rules or time difference betwee exams. Can anyone advise please