MTNL Delhi How to read Usage Details?

[ProblemSolverISP]

After a lot of hassle, i was able to login on MAHANAGAR TELEPHONE NIGAM LIMITED
How do i interpret my readings? In FUP plans the Grand Total Volume(53,591MB) is counted or Grand Total of Download Volume (36,551MB)?

Also what is the meaning of "Usage Limit" and "Unbilled Usage"? I hope they wont bill me Rs. 21,000 this month

Here is a screenshot of my Usage Details page -

Thanks for helping!

PS- Missing Airtel's -easy to read- smartbytes page, but also loving cheap 8mbps plan

 

[x720]

Total usage is used for FUP.

 

[ProblemSolverISP]

@x720 Okay, thanks. Do you have any idea about Unbilled usage and limit also?

 

[x720]

If its unlimited, its unlimited.