Clarification needed on FPGA bitstream flashing

[ferdaus89]

1. I am not using J11- JTAG pins
2. When i use ".ttf" file to program SAMD and FPGA using Arduino IDE, where does the fpga bitstream stored ? IS it stored in FPGA -EPCQ16 SPI Flash ?

Arduino MKR Vidor 4000 et FPGA

This website says in section III - ".ttf" file is mapped to spi FLASH. I need clarification on this if its correct or not.

3. I used USBBLASTER 1.0.0 library on SAMD, and installed intel usb blaster to work it out with quartus. so in this mode when i program ".sof" file why the bitstream doesnot stays after system reset?

after some searching i found someone told about using J11 and JTAG blaster method:

Procedure to Program FPGA FLASH on MKR Vidor 4000

Hello, I put together a brief how-to guide on programming the FLASH that's attached to the FPGA on the MKR Vidor 4000. I thought this could be helpful to some that are interested - it requires using the USB-Blaster via J11. Regards, John W. MKRVidor4000FPGAFlashProgrammingProcedure.pdf (432 KB)

now in vidor schematic SAMD and FPGA both are connected on same JTAG - J11, so at this point i dont understand, if i used J11 and upload bitstream to FLASH, why its not possible through SAMD - USBBLASTER ?

I know FPGA contains JTAG but does it also contains JTAG with SPI IP ? i want to understand what's the difference between no 2 and 3 i described.

Thanks