DLA to PIP reduction

Hi, I'm a registered member but I'm struggling with this at the moment, 2 brown envelopes in the past few days, I hope you can help. Briefly, I was on Higher Care and lower mobility on DLA, invited to claim PIP, any amount of RMN, CMHT specialist care plans, psych evaluations etc sent in with application completed as per B&W guidelines and a ReThink advocate attended assessment where I was in an overwhelming state of distress all through it.
Decision letter end of last week no care awarded(only 4 points) but standard mobility.
ESA letter arrived this morning, SDP removed as no longer receiving care component of DLA/PIP.
In total £150 pw removed and my situation had not changed and I know PIP is different to DLA but I should have qualified for 28 points on care not 4.
I have Complex PTSD and OCPD and believe the mobility was only awarded as a result of the DWP losing the High Court case.
I also know there is approx a 70% success rate at tribunal but what I really need to know is:
1. How successful are Mandatory reconsiderations or do these in the main just rubber stamp the initial decision
2. How long do MR's take, I know I have a month to get the request in
3. How long do tribunals take
4. How do Welfare Rights assist with tribunals
5. Would CAB be a better option to Welfare Rights to assist with tribunal

I have an advocate from ReThink calling to see me on Friday but its not their specialist area and it was suggested they would not be able to help at tribunal that I would need Welfare Rights.

I'm sure these type of questions have been asked before but I am in such a dazed state.
Thank you
Robin

Thank you Gordon - that's a lot worse than I expected.
Would the MP have any sway in timescales - I spoke to the MP's assistant who advised that MP's have a complaint hot line to the DWP for PIP, ESA etc
Robin