Can LCWRA status be carried to NS-ESA

Client advised to claim UC when they should have claimed NS-ESA and has now been awarded LCWRA, wife has just turned pension age so their UC has been reduced due to her pension well below what he what have got had he claimed NS-ESA and been awarded SG, I know your status moves with you if you go from ESA to UC but does the same apply if you go back the way or would he have to start the assessment journey all over again? Still within the time limit to benefit from NI conts paid.

And on the same subject, are there any checks carried out when a UC claim is made whether the person would be entitled to NS benefits if they have no UC entitlement?

Yes, works both ways: see Reg 16(1)(h)