I was advised that if you have over 12,000 miles and you want an extended warranty, its better to wait til the end of the standard warranty period because the warranty purchased after 12,000 miles changes from being an extension of the warranty term (as it would be if you bought it when the car was purchased), to a warranty that basically becomes co-terminous with the factory warranty and only kicks in for the period of time beyond the remaining term of the factory warranty. In other words, say I bought a 5 year 70,000 mile warranty today with 19,000 miles on my car. It would not be 70,000 miles on top of the factory warranty, instead its covering me only until I get to 70,000 miles (or for the additional duration of time), not extending it.
Can anyone confirm this as being true with certainty? I got burned once by GM with this before.
Also, if this is the case, until what point can you purchase the warranty? Can you buy it at the last day of or last mile of factory warranty coverage?
Thanks!