Hi there, sorry we obviously didn't catch this in time, what did you go for in the end?
By the time my DD was this age I tried not to worry so much if she was a little short on day sleep. I might have started the BT routine slightly early in case she was ready and to prevent a sudden tip over into OT but other than that she can often self regulate by sleeping in a bit in the morning or having a longer nap the next day.