Like that map also shows current overall and women’s record.
It's good that they've added the 'current record' dot.
(For anyone who's not looked, the 'current record' dot is moving at the pure average of Mark Beaumont's total distance divided by his total elapsed time, which gives 9.60mph.) It provides for lots of ways to look at how the attempt is going.
One of those ways is to calculate out how far ahead of the dot Lael needs to be at the point when she reaches a flight. For the first one, Halifax to Lisbon, she'll take six hours flying,; add airport time at each end and contingency for arriving in time; so that's probably at least twelve hours total time for the flight. Conversely, the Beaumont dot on the tracker will reach Halifax and appear immediately in Lisbon, and carry on moving at 9.6mph. So in order to stay level after the flight she needs to be twelve hours at 9.6mph ahead, or 115 miles, approaching the airport in Halifax. Right now, she's 109 miles ahead, and that's been steady for quite a while now, give or take a mile or two. The longer flights obviously require a greater margin.