Regarding this I contact to the International office and He says:

>The regulations allow you to have a gap no longer than 5 months between
>the ending of your last program of study (or OPT) and the beginning of
>your next program of study. Between October and January there is less
>than 5 months, so you should be fine.
>
>If you return to Nepal in October you would be able to travel back with
>the F1 visa that you have (if it expires in 2011). You should be OK
>traveling back, as long as you have an I-20 for your new program of
>study.