10 months should be good enough. And if you still have worries - do not get into any other legal trouble, or file N400 before completing 5 years of GC. CIS has 5 years to revoke a GC - actually start proceedings to revoke the GC. After that their powers get a bit curtailed - not that they can not do anything if they can prove outright fraud and such. However, their motivation decreases and the complexity increases - hence my advice to stay out of trouble, and file N400 only after completing 5 full years of GC.