This isn’t only numbering schema - it is totally different concept of road network in Serbia.
Look at the map: http://www.skyscrapercity.com/showpost.php?p=92155474&postcount=2583
There are a lot of critics about it, but it is the only official categorization.
Any evidence of road signs being replaced already?
Just thinking we should maybe not rush with the work until they are…
The old numbering schema was active for more than 35 years and transition could not be achieved over night - AMSS is still using the old schema.
Look at those links:
http://www.amss.org.rs/index.php?option=com_google&view=standard&id=4&Itemid=181
http://www.putevi-srbije.rs/index.php?option=com_content&view=article&id=2860:130812-radovi-na-drzavnom-putu-ii-reda-broj-128-deonica-golubovac-donji-milanovac&catid=34:odrzavanje&Itemid=1632&lang=sr
http://www.putevi-srbije.rs/index.php?option=com_content&view=article&id=2824:090812-obustava-saobrajaca-na-drzavnom-putu-ii-reda-r-267-ugrinovci-dobanovacka-petlja&catid=26:obustave-saobracaja&Itemid=1584&lang=sr
http://www.putevi-srbije.rs/index.php?option=com_content&view=article&id=2817:080812-drzavni-put-ib-reda-broj-21-m-19-deonica-debrc-misar&catid=26:obustave-saobracaja&Itemid=1581&lang=sr
The M-roads are now in a good shape except M9.1 (missing part in Kosovo), M21.1 (missing part in south Central Serbia), M22.9 (does not exist in reality). The length information come from Wikipedia.rs and I am not sure how outdate the informations are.
https://wiki.openstreetmap.org/wiki/OSMonitor/Serbia_Major_Roads
When the new schema becomes more clear, we can run statistics for it also.