I've just started a batch with that number, this last few days, but as yet I haven't noticed anything untoward. I don't think!
5.1 fasting this morning.
Caffe Nero porridge with soya milk and cinnamon.
1 hour later 6.7
2 hours 5.5
Whilst I don't like the idea of a 6.7 I think it's in range so I...