Oh my I know about inconsistent schedules!! You have my sympathy. I've had to learn to roll with it too, though that's not my natural inclination. Sorry she's ill, though the side effect of long naps is pretty great
I went back to work when DD was 13 months and she was pretty much transitioned to one nap by then. I worked a similar pattern to you - Mon/Wed/Thurs. On days she was at nursery there was a set nap of 11.30/45 so what we did was just set that as our naptime at home (regardless of wakeup) and then set BT at about 6pm to begin with. Usually nap at nursery was really short, but we pushed on to 6pm unless it was a complete and utter disaster ie less than 30 mins. At home we kept same naptime, never woke in morning (unless we had to) and she would take some huge 3h naps to catch up. And still generally go down for the night by 6pm or just after. Over time we were able to push normal BT to closer to 6.30pm, and then had to move nap a bit later at home from around 17/18 months.
