HSMP FLR extension to cover 3 months shortage

Is anyone in the following situation?

HSMP initial approval for one year. Arrived in the UK after 3 months Applied for extension of HSMP under the new points based system, Got extension for 4 years. Now it I will be 3 months short of 5 years to apply for ILR. So, I need to apply for another extension.

(1) Although I qualify for Tier 1, I want to go through FLR HSMP JR route to simplify the application process as I need to show only economic activity. Given my situation above, can I apply for extension taking advantage of the judicial review?

(2) If I apply for FLR HSMP JR, would I get extension only for three months to cover the 5 years period or would I get extension for further 3 years?

(3) Is the FLR HSMP JR applicable for extensions only upto 5 years? Can I use this to seek extensions beyond 5 years?