Scenario 1: An employee is off for 8 weeks from 1st January so is paid 4 week full pay 4 weeks half pay. They return to work then go off sick again for 4 weeks the 2nd week of the following January.
A - paid 4 weeks full pay (because, at the start of the 2nd period of sickness, in the prior 12 months they have had 4 weeks half pay and 3 weeks full pay, and each week a full pay drops off from 12 months ago - so they get the 4 weeks full pay again)
B - paid 4 weeks half pay (because they have had 7 weeks off in he last 12 months so they are at a half pay week i.e week 8 of 8, and they will be at week 8 of 8 for the full 4 weeks, because weeks will keep dropping off at the other end)
C - something else
Scenario 2: An employee is off for 60 weeks continuously Jan 1st onwards (and we assume they're not sacked). In week 2 of the following January...
A - they get nothing because it's one perod of sickness
B - They go back into benefit at full pay for 4 weeks then half pay for 4 weeks, because every week that goes by, 1 week of drops off from 12 months ago - the first weeks to drop off are the full pay ones, then the half pay ones
C - They go back into benefit but at half pay because they have had 7 weeks off in the last 12 months so it is calculated that this new 8th week of sick is at half pay - because the policy says weeks 5 to 8 are half pay. This half pay would continue for 8 weeks (as each week a prior paid week drops off from 12 months ago so they have only had 7 weeks pay as each new week start), After 8 weeks, they will have had 8 weeks in the last 12 months so sick pay is exhausted.
D - something else