"bicycle=dismount" tagging in OSM

Hello, apologies for the burst of questions. Last one.

When mapping routes with all vehicle prohibitions (including bicycles), I have often added bicycle=dismount as suggested by http://wiki.openstreetmap.org/wiki/Road_signs_in_the_United_Kingdom#Vehicular_type_restrictions . I've also used it where a very short footway (without restrictive barriers) allows a significant shortcut for cyclists. However, I've noticed that bicycle=dismount means gets rendered as a cycleway on cycle.travel . Am I better off just tagging bicycle=no and trusting that cycle routers such as cycle.travel will be clever enough to direct cyclists to walk their bikes along pedestrian paths where there is a significant time saving?

"Find Photos" link question

Does the 'find photo' link just search for nearby photos uploaded on geograph.org.uk? If I wished to add new photos of cycle routes, is the best method to add them to Geograph? How often does cycle.travel check for new photos?

How often is the map/routing information updated?

Hi, I'm fairly new to using this site, though it comes highly recommended. Apologies for asking three separate questions in one day. No more I promise!

Roughly how often are the maps/routing updated to account for change in the OSM data?