Is it okay for elderly to eat meals erratically?

That's about the schedule my mom followed when she was living with me. Since I went to work at 8, I would cook a bowl of oatmeal for her which she heated up when she got up mid-morning.

Normally this schedule wasn't an issue unless we had something to do say mid-afternoon - like a doctor's appointment - when she would normally be eating. I think that is a fine schedule for your Mom.

I'm not sure what's wrong with those times. They seemed spaced-out enough, too.

Don't worry. She's eating, that's all that matters

Don't worry about when she eats just as long as she is eating healthy.

You can't force her to eat on your time unless she's a imate in jail requiring chow time.Be glad she's eating.Most elderly people eat small like a little bird as not getting enough in their system.Once elderly people get dementia that's when it becomes a problem as remembering when and if they eat.As long as she is eating enough that's all I would be worried about.I would say eating before bed time isn't a good idea.For what your explaining,Sounds like she sleeps to late in the mornings."10:00am breakfast".Sounds like to me she is staying up too late at night and sleeping in to late.All the elderly people I ever known wakeup before the birds singing and go to bed by 6 pm.Sounds like you need to have her go to bed earlier and wakeup earlier in the morning to enjoy the day.Timing is off is all it is.
Be thankful she eats.
best,