In 1996 we still had prescriptive legislation and code based enforcement so it was pertinent to give 2 years to phase implementation. Not only that the prescriptive regime that existed was as good as! and with hindsight better than that which was implemented with EC Directive 92/58.
I do agree that the EL industry has a lot to answer for the confusion and it is why I have consisently said that fire safety signs should not be considered as part of an emergengency lighting system.
The situation is quite different now, using graphical symbols that we know are likely to be misunderstood, likely to be ignored, likely to reduce ASET requires risk assessors to note as a significant finding and recommend replacement schedule. This schedule should be appropriate to the purpose group of the building, in some cases it might well be appropriate to just remove all the signs, if the building layout is very familiar to all occupants, however in public buildings and hotels I believe replacement should be a much shorter time scale.