Lol shows what I know! My reason for this line of thinking is, I used to only use 19-19-19 at fall seeding time because the fert reacted fast but was gone fast, then I would follow up quickly with a winterizer and had great results. Well I did soil tests on my properties and found that my Phosphorous was low across the board and the Lesco guys recommended starter because it was slow release and would be around longer...
I don’t like seeding and fertilizing at the same time regardless of what your using
Think about it this way, you have existing grass, you seed and fertilizer with a All quick release fertilizer, it feeds for two weeks, it takes 10-14 for germination of your seed, so all you have done is feed your existing grass and it’s gone by the time your seed germinates and starts growing
That reason is why you see so many fescue yards that don’t mature until spring
Here are my recommendations
Aerify, seed, first couple weeks of September, after the grass germinates and starts growing several weeks later apply your slow release starter fertilizer, it will release all the phosphorus first and your seedlings will take up what they need immediately and roots will start forming great, the slow release nitrogen will benefit the new grass and the old grass at this time, releasing over a period of about 4-6 weeks
I like to feed the grass again middle of October to help in the maturing of the seedlings, if you need phosphorus apply another round of slow release starter
I then feed again with a high nitrogen semi slow release 25% or so around December 1
Your grass will be mature after this application, no more nitrogen until spring, too much nitrogen in January/ February will cause spring disease
March 1-15, apply pre-emerge with a low amount of Nitrogen, then no more nitrogen until fall