I'm confused. Did he plant fescue or did he plant lovegrass?

You wouldn't expect success if you plant lovegrass in december and likewise you wouldn't want to plant fescue seed then never water it.

But this is what builders do. They don't care.
Don't even waste time trying to get your builder to do this right because they will put in the cheapest most horrid weed and it will look like crap.

This is easy enough to do yourself but if you want to get a landscape to do this you can. First select something that is attractive that does not require mowing. I highly suggest shrubs and trees but perhaps some grass could be mixed in. There are few grasses as beautiful as creeping red fescue for a hillside in CA. You might look into that. IT is not the same as tall fescue and not the same as Weeping lovegrass... which is really not that attractive IMO.

You could make a really beautiful planting here with some curved planting areas with groupings of assorted low maintenance trees followed by a mid ground of shrubs then in the foreground you could use something like blue rug juniper then towards the bottom you could use the grass.

realtor, who is also builder's wife, said love grass. later learned it was fescue--kentucky 31 most likely. the second time was also with fescue. ugh. i know i won't like it. i do like the look of sideoats. about two feet and develops oat like seeds that stay on--feathery effect which likes nice with the butterfly weed. do you think i should pull the seed germination mat up and start bare soil? should l place straw over top? last, will a soaker hose do the job?

I don't think I'd start tearing everything up. I'd just add some more seed, of a variety that you like, as a stop-gap measure.

At the moment, it sounds like you've got a bare berm. That won't last long, as is, will it? Put something down, sideoats or otherwise, and spray it as needed. Fertilize it as needed. But get it growing.

For steep slopes, seed blankets are great. Nothing wrong with K31 if you don't mind the appearance. It is tough grass and has deep roots to prevent erosion. I noticed a nearby developer using a seeding blanket held in by a thin guage mesh poly netting. I don't think straw would have been adequate with the incline.

We had a retaining wall installed on a steep slope and erosion control mats are in place. The slope has the mat with oats (which came up great!) and the lawn behind the wall has the mat with grass seed, which has started to poke through. The mat is hay and poly mesh, a bit of a tangle/ trip hazard.

Should the blanket be pulled up and when? The last time we had a blanket for lawn, it seemed the grass was starting to rot, so we pulled up the mat and the grass came with it. Some of that mat (from a year ago) is still around, so it didn't seem to degrade very fast. We don't plan on pulling up the mat on the slope with the oats. Any advice?

I would pull up the mat once the seed has germinated but I like to save and re-use those expensive straw blankets.