UC full service (new claim), waiting for WCA and undertakes some work - effect on UC

Comrades,

Would be grateful for your advice and input on this case.

Facts

Client claimed UC in full service area in February.  Had a sick note signing him off to May.  Client has long standing depression and also receives standard rates of PIP (daily care and moving around).  UC Job coach said has to search 35 hours a week despite being in waiting period for WCA and getting PIP (hours could have been reduced to reflect long term health condition), and allowed his work search to be limited to his usual line of work only (entertainment).

Client then got some entertainment (self-employed) work for 4 weeks - 18 hours per week average, net profit £135 average per week (£540.00 for the month).

NEW job coach now insists that his waiting period (for WCA) has to cease even though the GP wants to give him another sick note restricting work duties not signing off completely and client says he struggled to do the work and was having treatment/therapy throughout.  He has other medical evidence which suggests he is at risk.

I have advised him on limiting work search hours, also on the treatment of his limited capability for work and earnings IF he is still his waiting period and passes a WCA (does not lose LC for work as is receiving PIP - Reg41(2) and (3), UC regs)

Questions

- What is going to happen to the waiting period?
- What is the relevance of the sick note? 
- Does he have to have one in order to be placed in the waiting period for WCA, and if so how long must it last ?  It appears from the regs that it is only relevant for the first 2 weeks if at all (reg 99, UC regs)

Many thanks in advance.

In solidarity,

EKS.