How long should it take to get an SDP backdated payment made?

Hi,
client been awarded an SDP and it’s been backdated to 2016, however, the backdated payment is not forthcoming.
Does anyone know if this has to be paid within a certain timescale? I’ve checked all my resources and can’t find anything about how long it should take to be paid

Many thanks

I’ve had a client in a similar situation.  We’ve been chasing the SDP to be added to the claim since August 2022 and this has only very recently been done following a complaint, but we’re still waiting for the backdating.
I’ve been told that the issue is being dealt with the GMS team at Bridgend, but that all staff have been indefinitely moved off this work to answer phone calls.  I spoke to one such member staff in one of my many phone calls!
Next step will be a letter before action threatening Judicial Review, I think.

Wow, that is a long time and nowhere near as long in my case. I’m inclined to refer it to the MP.
Thanks for the information Helen