Five shorter days preserve daily contact
Being present every weekday may suit roles with a daily handover, morning coordination or frequent short decisions. It can reduce the need for a colleague to hold matters overnight. The drawback is that commuting and setup time still occur five times, and work can spill beyond the agreed finish if boundaries are vague.
Four days create a clear boundary
A full non-working day can make appointments, care responsibilities or recovery time easier to plan. The team, however, needs a clear route for matters that arrive on that day. Recurring meetings may also cluster in ways that make one chosen day difficult.
Test each pattern against real events
Take a typical month and mark team meetings, customer deadlines, handovers and peak periods. Do not rely only on an ideal week. Ask what must happen in your presence, what can move and who needs to know when you are unavailable.
State the boundary in plain language
Whichever pattern you propose, define start and finish times, breaks and availability outside those windows. “Usually offline” is harder to protect than a shared and specific schedule.