Sorry but the rules are very clear. Income Support is the priority benefit in law and so a £20 limit within a 16 hour working week. Anything over the £20 comes off IS on a penny for penny basis. Anything over 16 hours and goodbye IS. Carers Allowance, for those NOT receiving IS, has no hours ...
I'm so sorry Myrtle. It must have been a terrible time for you both.
(((hugs)))