I have this issue too but I don't mind late drop offs.
All the parents are told clearly what times we are at the bus stop and everyone seems good at working around to either meet us at the bus stop, come before or after so it is no big deal.
If a parent wants to delay the day - it is better for me. I can get more stuff done before they come so I don't mind.
Sometimes the child will miss a craft or a trip to the park but there is always another day.
I am fully supportive of parents spending as much time as they want with their kids...it works out well for everyone
I like the idea of leaving a note on the door and letting the parent know where to find you if they don't show up...or have the parent call you.
I have one family call me almost every morning to tell me whether they will be late or meeting me at the bus because their mornings are flexible. I don't sweat it. communication is key and I appreciate that they update me so I don't have to wonder.
That said....one of the most annoying things I have found is that when you sign a new family they get PANICKED reading about late charges in the contract so they write down a really early drop off (just in case they need to drop off early) and then put the latest possible drop off. I think the parents want to cover their bases and say "well I wrote it in my contract'. So I have one parent who wrote an 8 am drop off and an 5:45 pick up. The actual drop off since the last 8 months has always been 8:30 and the pick up at approx 5. It seems all the parents do this just to avoid me complaining about lateness or being charged. So for instance this family can pick up at 5:45 without me being able to say anything because that is what they wrote and signed with me at registration. I basically have to look at the 5 pm pickup as just something I can be happy with when it happens 99.9% of the time.