Hi ClaireMallee,
You’ve laid out the chaos clearly, and you’re on the right track with both options. The support advice is spot on here. Match the negative and positive pay runs so they cancel cleanly, making sure the count is one‑to‑one. If there are extra negatives from those double reversals, create matching positive correcting pay runs to offset the leftovers so your STP, Payroll Activity and P&L settle back to normal. If that feels like a slog, restoring a clean backup from before the date mix‑up and re‑entering the affected pays is absolutely a valid path and often simpler, especially with 17 staff and multiple duplicates floating around.
Cheers,
Doreen