Does this help
QUALIFYING CONDITIONS IN DETAIL- THE CARER
Employment condition
The Carer must have been employed in full-time employment for at least eight weeks, either consecutive or not, in the 26 week period immediately prior to the commencement of the Carer's Benefit claim.
Full-time employment in this context is defined as insurable employment for at least 16 hours per week or 32 hours per fortnight.
This condition does not need to be satisfied on a second or subsequent claim where a person was in receipt of Carer's Benefit within the previous 26 weeks.
As I understand it your JB would be frozen while on Carers Benefit and you would return to JB (the unused portion of JB) after say 12 weeks on Carer's. I'm open to correction on that