We have a HRV elegance , bought in April 2024 and are very pleased with it. The fuel consumption was 60 mpg up until the last couple of months when it has dropped to 57 with the same mixed use of long distance and short  trips. Is this cooler weather? We always drive in "B" 

I wonder if it is an 'average' fuel consumption meter and has settled down after a mixed driving style

if you reset it then it may go back to the actual consumption figure

Alternatively, a service may be due and the engine oil quality can contribute to a decrease in economy if the cylinder compressions are reduced with the oil not sealing the rings/bore as efficiently