Yes, it does do it in three chunks. (It took about five minutes to generate 524 bars of four tracks and a drum track on my computer.) It also inserted a C chord into bar 481. I had a G chord in bar 478 and a D chord in bar 485. So this behavior will repeat every 240 bars. I didn't do any regeneration of a short section of bars that crosses the 480/481 bar boundary, but I'm pretty sure the same thing will happen that happens at the 240/241 bar boundary.
Tom Levan (pronounced La-VAN)
BiaB 2021 Win UltraPAK Build 833, Xtra Style PAKs 1-11, RB 2021, Windows 10 Pro 64-bit, Intel Q9650 3 GHz, 8 GB RAM, 500 GB SSD & 2 TB HDD, Tracktion 6 & 7 (freebies), Cakewalk, Audacity, MuseScore 2.1 & 3.4, Synthesizer V