Additional PIP-related payments?

My friend who is on Universal Credit has recently been diagnosed with late-stage (terminal cancer). Because of this he applied for and has been awarded PIP at the enhanced rate daily living needs and the enhanced rate mobility needs. He received a letter to this effect with the amounts to be paid each week (£85.60 + £59.75 = £145.35), which he has been receiving. He is also receiving his usual UC monthly payments. However, additional amounts have been going, too, but of varying amounts and on no set day. My question is: are there additional payments he now qualifies for and, if so, would they be paid automatically or would he have to apply for them separately?

Gordon wrote: Mjke
The DWP wouldn't be paying anything extra in their UC unless they had applied for it.
Has a DS1500 been issued?
If it has then they should ask to be assessed under the UC Special Rules for Limited Capability for Work Related Activity, otherwise, Limited Capability for Work.
Gordon

Yes, the GP sent in a DS1500. Are you saying he can apply for extra money on his UC? How does he get assessed under the UC Special Rules? Thanks, Gordon.

Mjke