iPad Air 4 battery

I love my new iPad but doing a variety of tasks and using all suggested battery conservation techniques including going dark mode and reducing brightness, I tend to get four to five hours of running time - nothing close to the nine or ten advertised. And really... if I have to run the thing with the display turned off is that really what they’re selling at Apple these days? Just bought my son the old school iPad at the same time and he gets thirty to forty percent more time. Totally unacceptable. Apple did a diagnostic over the phone and claim all is good... except during the 30 minute call my battery drained twenty percent! I guess I’ll take it in to the one nearby Apple store but not expecting much. I love this thing and other than kicking me out of apps like pages from time to time it’s great. But it’s unfortunate to have to keep watching the battery drain and constantly have it on your mind. Not really a laptop replacement if I can only use it unplugged for half the time. Come on apple... fix it or don’t advertise ten hours.

Anyone else with this problem or had it fixed?