I agree with Tim,
I don't think you're losing it, my 2c has only ever settled just above the Matrix, I did the filling up every morning on my way to Portugal one year, then wondering where it had gone the next morning.
Eventually came to the conclusion that it was blowing it out of the overflow and finding its own level, 16 years on its still the same.
Series 1's don't have the seals anyway, 20 years and 36,000 miles later I get a bit of blue smoke!
But what I burn is negligible.
Brian
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