permanent visa

I was married to a japanese for 2 and half years(almost 5 and half years at present in japan) and divorced him last year because of domestic violence.i consulted the immigration about the ways to stay back in japan after my divorce and they told me that I can apply for permanent visa (定住者, teijyuuken).
On july I applied for permanent visa(teijyuuken) with all the required documents plus few more papers to prove that I was domestic violence victim. I was told it will take one month to process but today I got phone from immigration telling that I have to attend interview in october.
Does anybody know
1) Why it is taking almost 2 and half months when they said it will take only one month?
2)why i have to attend interview and what all questions will be asked, is it a normal procedure to call for interview?
3)if i am not granted permanent visa:
a)do i loose my present spouse visa(from divorced husband).
b) do i have to leave japan before the present spouse visa expires(i.e 2012)?
i will be very thankful to anybody who can provide me any information.

What you applied for is a Long Term Resident visa. It's different from Permanent Residency.

Some cases just take longer than others, especially if it's an unusual case. Mine took 3 months but I didn't have an interview and my application was rejected.

If you're rejected, you should be able to stay until 2012 but you should just ask them when you get rejected.

Your getting an interview is a good sign. That means you qualify. If you don't, they'll just reject your application. Don't worry and answer to their questions honestly.

Immigration is backed up nowadays. 3-4 months waiting is normal.

Dear guests,
thank you very much. you both made my morning and showed me some hope. have a nice day to you both.