We haven't made any changes in this area recently. The directions generated will depend on which Map Type you have selected, as we use different routing services for different Map Types - Google for Google maps and Graphhopper for non-Google maps. It looks like you may have been using one of the Google Map Types previously, as the directions from the Google's routing service do seem to include the name of the National Cycle Route.
Has something changed?
Last week when I was plotting routes the directions sheet would inculde the cycle path details - for example National Cycle Route 4, however I see that in the last few days these details are not listed at all in my directions for new routes I'm plotting.
There is nothing in my abrevations to suggest they should not be listed