Did the six-week fuel warning include naval reserves?

Did the claim of only six weeks of fuel remaining in May 1943 refer to fuels other than ship fuel?

Yes. It referred to aviation fuel and other supplies, while the Royal Navy retained its separate ship-fuel stocks.

The six-week warning is assigned to aviation fuel and other uses. Ship fuel is expressly excluded from that assessment. The distinction follows the Royal Navy's persistent accumulation of reserves, which could leave naval stocks plentiful while other fuel categories were under pressure.