In one of our courses, that uses the topcoll format, there are 7 sections: their id's are 1-6, and 110. Section 110 is an orphaned section, meaning that that in previous version of Moodle it didn't appear in the course since numsections is defined to be 6. In Moodle 3.3, the fact that the last section's id is not consecutive creates exceptions:
Notice: Trying to get property of non-object in /usr/share/nginx/html/aviv2017/course/format/topcoll/renderer.php on line 787
Notice: Trying to get property of non-object in /usr/share/nginx/html/aviv2017/course/format/topcoll/renderer.php on line 788
I get these exceptions for every id from 7 till 109.
When I change to any of the core course formats, such as topics or weeks, this doesn't happen.
I originally thought this was a problem with Moodle removing 'numsections' from version 3.3, and therefore posted on the Moodle development forum and even on tracker, but was told that this issue is related to the topcoll format.
I am using the 126.96.36.199 (2017042203) version of topcoll, on Moodle 3.3.