From page 32 of the report the central flight path to center of search area:
S10E95 on 2141 arc to S18E96.5 on 2241 arc is 561 miles @ 561mph
And from there to S30E97.5 on the 2411 arc is 831 miles @ 560mph
The autopilot works there for the last 2:30 but not further upstream for the earlier 3:12 —
It means that for the central flight path the plane averaged 377mph over the first 3:12 for 1208 miles and then 560mph over the last 2:30 for the final 1352 miles.
That’s not exactly autopilot —
From page 8 of the Report:
N7E103.5 [point of turnaround] @ 17:19 to ~Penang Island @ N5.3E100.3 is 251 miles
From there northwest to N7E95 [where the plane was headed above Indonesia] is 382 miles.
That’s a combined distance of 633 miles taking 70 minutes @542mph at the point of the 18:29 frequency burst.
It’s hard to believe that the plane could have flown faster and gone any further north or west than ~N7E95 — a point that clears Indonesian radar and gives him a straight shot south.