thekite
Damn fine flying, Muffinman,
I have had that particular problem twice before, once in a Hughes 500 - just landed out and asked Bankstown Tower to get more oil sent out. Problem was a leaking #1 compressor seal. The engine drank it's own oil.
And once out over the North Sea, in a twin. We just pulled the sick engine back to flight idle, and watched the pressure stabilise.
Oil Temp actually dropped with the oil pressure!
Turned out that #8 scavenge pump had NOT been fitted with the requisite O ring. And the engine drank it's own oil.
Theory is that any turbine engine will run for quite some time with no oil pressure - until you reduce power whereupon it will immediately seize.