Appealing PIP but now facing migration to UC

Hi

My sister is starting the managed migration process from IR-ESA WRA Group to UC.

However, her latest PIP review has just come back and denied her claim. She is currently going through the Mandatory Reconsideration process before appealing.

Until January 2025, she was receiving:
PIP (daily, standard & mobility standard)
ESA Standard allowance
Plus ESA Disability Premium (due to the PIP award).
I'll call this Receipt A

Currently, she is just receiving ESA Standard allowance, because she's lost her PIP. (She doesn't get money for being WRA Group)
I'll call this Receipt B

She's now received a migration notice for UC. I believe under UC, she would receive:
UC Standard element
UC LCW group element
I'll call this Receipt C

However, if she still had her PIP (as per Receipt A), she would also receive Transitional Protection of ~£45.

My question is:
If she migrates now, without having the PIP Disability Premium under ESA, and then the PIP gets restored once she's on UC, will the Transitional Protection still kick in?

Or is she better off asking for a delay in her ESA-UC migration until the PIP issue is resolved, to ensure the Transitional Protection is added to her eventual UC claim?

Hopefully that makes sense. Thanks for your help!