On our staffing rota all teachers are required in school exactly the same number of days each week, regardless of full time or part time. Some are part time and now in 100% of their usual days, some are in 80% of their usual days yet full time staff are only in 40% of their normal hours. Everyone also has online learning to respond to.
Given part time staff are not working longer than their usual hours I wonder if they are told you get over it, even though it feels hugely unfair full time staff are in less than half their usual hours and given 60% of the week at home.