I read aloud everything for the guides you've mentioned, since our dc are quite young when doing those. However, once the dc begin BHFHG, they begin reading their science and reading, as well as being independent in other areas. In PHFHG, they read more on their own, and in CTC they're even reading the history spine. So, each year is a gradual progression where they take over more of the reading as they are more able. In those younger years, I do think it's important to model good reading for them, as they are needing to learn good listening comprehension skills - honing those skills rather than having to focus on the actual reading of it themselves. Here's the reading I have done for the guides you mentioned:
LHTH:
Bible Story 5 min. daily
Devotional 5 min. 1 x a week
about 5 minutes total daily
LHFHG:
Reading about History: 5-10 min. daily
Storytime: 5-10 min. daily
Science: 5-10 min., usually 2 times a week
Devotion: 5-10 min., usually 2 times a week
about 20-30 minutes total daily
Beyond Little Hearts:
Reading about History: 10 min. daily
Storytime: 10 min. daily
Science: 5-10 min., usually 2 times a week
Devotional: 5 min., usually 1 x a week
about 30 minutes total daily
I like to rotate the reading with the activities, and that has made each reading kind of a special "cuddle on the couch" time. Each reading in itself is bite-sized, but done all in a row might feel longer. I'm not sure if you are still doing LHTH and Beyond, with just a few parts from LHFHG? Or maybe you have decided to do all 3 programs in their entirety now? If you are doing all 3 and feeling like the reading it too much, you could combine your dc for Storytime. That would be an easy way to shave some reading time off if that is your desire. Otherwise, your 4 and 5 yo's could just do LHTH and your oldest do Beyond this year, and that would be super easy to do. We've found the reading and hands-on to be a nice balance. Maybe rotating the reading with hands-on, or combining your 3 dc in 2 programs (especially since there is only a 3 year age span between the youngest and oldest) would be a good idea if the reading feels too much. I have to say having looked at Sonlight, the reading in HOD is a breath of fresh air in the reading demands department.

Maybe you're like me and haven't done as much reading out loud to the dc through the summer - then starting up again takes some getting used to? Especially the first day. It usually just takes me awhile to get into the routine of teaching school again. Be sure to give yourself that grace to begin teaching 3 little ones again! HTH!
In Christ,
Julie