Have they asked prior for bank statements, even after the first time you applied (FM3)?
If you have been asked to show prior statements then I would show the maximum amt of time.
I am not sure that an FM3 then applying for a temp resident would count as being your 4th year.
First time I made my FM3, they wanted 3 months statements, then last time for my Temporary Residence card for 2 years they asked for 3 months again. Never 6 months. Never heared of anyone beeing asked 6 months anyway, but I thought I ask on here since rules seem to change every year.
How about you, didn't they ask for any statements at all when you made your renewl?
About my FM3, they told me it'll count for the 4 years.