Land Rover Repair: air suspension, side spring, air suspension

Question
We have a 2000 4.6 HSE Range Rover.  At first, I noticed once the truck was turned off, the front passenger side would lower all the way down while the rest of the truck was still sitting up.  After it was cranked up, it usually would level out.  Now, the truck is lowered all the way down and will not lift at all.  Which also results in a warning saying "max speed: 35 mph".  What could the problem be?

Answer
This is definitely a leak in the front passenger side spring, which overcame the capacity of the compressor.

The compressor could compensate for the leak for a while, but either the leak got bigger or the compressor has worn down to a point where it can't keep up.  Since that spring wouldn't lift the ECU went into fault mode to force a repair.

The springs can easily be replaced and the compressor can be rebuilt.  Since one spring is leaking the other 3 are likely close.  You'll save time, hassle and shipping costs to replace all 4 at the same time.