Would not start... when hot

Hi folks, I have a question with regards a starting issue...

Rode for about 60 - 70 miles yesterday with the lights on (first hot day @ 30 Deg. C) and bike temp was showing 107Deg. C and I'd stopped for around 10 mins and went to start it again put all I got was a click and a bit of a movement from the starter. All the symptoms of a flat battery. I got a jump start via a car and jumper leads and it started immediately. I then rode home 10 miles with the lights off and parked up with no issues. AFter about an hour I went outside to put the bike in the garage and it started immediately under its own steam. One checking the battery voltage it was 12.5 with the engine off and 14.2 with the engine running.

Q: Would the lights drain the battery sufficiently to prevent starting?
Q: Would the ride home without the lights on be sufficient to fully re-charge the battery?

Rectifier seems OK in my opinion, so what might have gone wrong?

Thanks, Rod