That's exactly correct You get a new decal to affix to the outside and a new Certificate of Conformity. I have done it for tge last 2 caravans I have owned. Its a con!
Nothing actually "alters" on the caravan The Statutory VIN plate in the gas locker shows the higher weight from new anyway.
It's a bit of a throw back to the time you needed the +E category on your driving licence to drive a rig over 3500 kg. By having a lower MTPLM it widened the market slightly in regards to who might buy the caravan and still remain under the magic 3500kg
The "upgrade" just boosts your available payload by about 50kg
But don't forget that Bailey quote the MIRO
Without a leisure battery (which they say you shouldnt operate the caravan without
) so one of those takes 25 - 30kg off your payload to start with, then if you have amotor mover that's another 25-30kg so the upgrade is wiped out before you start. If you fit a battery and mover, and dont go for the "upgrade" you start out with only about 100kg available payload (gas bottle, crockery, clothes, food soon exceed that figure) Crazy isn't it?
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