Hi Nimish,
Yes, I understand that now. lsusb just reads the info. I had to create a rule and follow the TN-101 note that you mentioned. We had to reboot the system apart from the steps mentioned in that application note from FTDI. We can now see devices getting mounted as /dev/ttyUSB*There is nothing different we did to create a rule for the multi-channel device. It shows 4 ttyUSB devices with a similar rule as yours. I have attached the file here for reference.
Excellent! Cheers, Dave