In Tuscaloosa, each jock was given two new styli every 90 days. If he tore them up before that, he hadda produce his own. (The jocks also wore coat and tie to remotes.... remember the Day?)
The music guy dated the 45s, and harassed the record reps for reservice on a regular basis. He'd check the dates on everything in the bins regularly, look at the 3x5s, and replace the records after about a hundred spins, about the time the cue burn was beginning to become audible. Place sounded real good.
For the children amongh us, in the day of playinjg 45s, it was common to put a bin for each song category either in front of the jock or above the turntables, with a 3x5 card on it. 45s were kept in heavy green maniia sleeves. Each category was color coded with stickon dots, and the clock was dotted. Take the front record out of the bin, cue it, and when you start it, put the date and time on the 3x5 card. When you replace it, it goes to the back of the bin. Simple system, worked great. Want to speed up the hot rotation? Take three records out of that bin, put new colors on them, and move them to the recurrent or older bin(s). Does this date me?