SDP and Transitional element

Hi, can anyone help with a couple of questions on SDP and transitional payments please. Whilst receiving ESA Income and Contributions based I qualified for PIP Daily Standard and Mobility Higher rates on mandatory reconsideration which was backdated. ? Should I also receive SDP inline with PIP? And, if so, should this be backdated to PIP start date? When I moved home I was transferred to UC to claim Housing Benefit so lost ESA Income related but kept ESA contributions based which is deducted from the UC, PIP remained in place. ? Should I also be entitled to the transition protection payment on being moved to UC? So far I have been unable to get through on the phone to DWP so I have written to them several times with no response so far. Any clarity on my situation would be very much appreciated 🙏 Additional information and advice is also very welcome. Thanks in advance