You should ideally stop eating within 12 hours of when you want to wake up the next day.
https://sleep.med.harvard.edu/news/229/Harvard study finds fasting resets circadian clock
It has been found that the body actually has a time clock that is governed by when we eat. Thus the circadian day and night cycle is actually over-riden by our stomach. This actually makes sense as from survival/evolutionary adaptations the body prioritises food over sleep. Thus going to sleep hungry or slightly hungry will guarantee that you are hungry the next morning and thus your body will 'wake you up' so it avoids starvation.
Eating a heavy meal and then going to sleep to attempt to wake up early the next day is essentially inducing jet lag & probably causes delayed sleep phase syndrome and persistent daytime sleepiness. You throw your entire body clock out of sequence.
Eating large meals late or close to sleep is also associated with obesity, sleep apnea, reflux, snoring and a range of health problems.
Recall our grandparents - they would always eat around sunset (6-7pm). With the fast pace of technology we have modified our lifestyles but this hasn't been a good change.
Ideally if you don't have time to eat dinner early you should just have a sandwich or just snack on a bit of fruit and not eat a heavy meal. It is better to eat heavier at breakfast or lunch. Ideally you should not be eating large/heavy meals after about 3pm if you struggle with daytime/morning sleepiness.
http://news.harvard.edu/gazette/story/2008/05/study-identifies-food-related-clock-in-the-brain/
“A period of fasting with no food at all for about 16 hours is enough to engage this new clock,” says Saper. “So, in this case, simply avoiding any food on the plane, and then eating as soon as you land, should help you to adjust – and avoid some of the uncomfortable feelings of jet lag.”
The same principle applies here. If ones sleep clock is out of rhythm a 16 hour food fast may be necessary but to maintain and enforce a healthy sleep routine one should probably avoid meals 12 hours before waking up and eat lighter in the evening.
I think with ME/CFS the body has problems with energy and metabolism. Sleep is needed for recovery, thus eating late is going to cause problems as sleep will be even more non-restorative as the body has to use a lot of energy to digest. Thus it would probably be well advised to follow the advice that Harvard has produced to maximise sleep quality. This will give the body the best chance to recover.