PIP claims ending or renewing

I am finding recently that long term PIP awards made by Tribunals seem to be either renewed by DWP in the normal way by planned intervention (AR1 form etc.) or are just ended with an invitation to reclaim letter sent about 14 weeks before. I am talking about awards of more than 2 years in length. I can find no discernible reason why they are being treated differently and I have not been able to get any coherent explanation from PIP either.

Does anyone know what the current guidance is or why there is this seemingly random difference in how awards are renewed/ended?

The guidance is here : https://www.disabilityrightsuk.org/sites/default/files/pdf/Award%20period%20guidance%20-%208%20August%202018%20%282%29.pdf

Presumably in a Tribunal case, the case manager still has to decide how to categorise the award because the FtT obviously isn’t using this terminology.

Thanks Elliot. I was aware of that guidance but in my recent experience it is not consistently being applied after Tribunal decisions and I just wondered if there was anything else that explains this? I get your point about CMs having to categorise the awards somehow but more than 2 years v less than 2 years is not really something I would expect anybody to get too confused about too often. Perhaps it is an IT issue?