The limits are in the STPCD. Whether you are inside them is left to you to work out.
Directed time is the time your headteacher can direct you to work: teaching, PPA, duties, meetings and briefings, cover, parents' evenings and open evenings. The School Teachers' Pay and Conditions Document caps it at 1,265 hours a year for a full-time teacher, and guarantees at least 10% of your timetabled teaching time as planning, preparation and assessment. Both are real entitlements. Neither arrives as a number on a screen.
So most teachers either never check, or check once in September with a spreadsheet and a calculator, then let it drift as duties get added and a twilight appears in the calendar. By the time it matters, in a workload conversation or a union query, the evidence has to be reconstructed from memory and a paper planner.
Teacher Task Manager totals it from the timetable you have already entered. Every teaching period, every PPA period and every free period is already there, so the calculator opens with your real week in it. Add your contracted hours, log the evenings you attend as they happen, and your position against both limits is a button away for the whole year.