Sarah Hinlicky Wilson has written a great post for Mockingbird on the trouble with the lectionary (https://www.mbird.com/2019/04/the-top-ten-reasons-the-lectionary-sucks-and-five-half-assed-solutions/#_ftn3).
The Advent has been making the same arguments since Paul Zahl was dean and made adjustments accordingly. The reason why we are preaching through 1 Corinthians is because the lectionary brings it up, but as noted, we have gone beyond in including that which the lectionary leaves out. This keeps us from preaching a hobby horse, but also makes us address those things in the Bible we would rather avoid. Wilson rightly diagnoses the problem in Mainline preaching when she says, ‘You can’t fix a homiletical problem with a technical solution.’
I would encourage all preachers to take what she writes to heart.