C to F is one measurement that really does not matter which you use. If the majority of books you read are from the USA then they will, of course, be in F. If we manage to get the BBBQS to the level where it has real international standing then the official “British” temperature scale in publicatiuons would need to be C - maybe with F in brackets.
Luckily with temperature it really makes no difference whether you use F or C as they both have different names and there is a simple conversion factor between them (Deg C = (Deg F -32) X 5/9). Unfortunately this does not also hold true for other measurements that we may use in BBQ recipes. In the UK a “pint” consists of 20 fluid ounces whereas in the US a “pint” only has 16 fluid ounces. This makes the UK “Pint” ~25% bigger than the US “Pint” and both US and UK still use 8 “pints” to the “gallon”. How many people using US recipes do not yet convert “US pint” to “UK pint” (UK "Pint" = US "Pint" X 1.25)? Have you ever wondered when using UK measuring jugs why your sauce tasted so watery or your marinade was not as thick as you expected?