I’ve never timed it, but I’m estimating over a half hour in? I forgot about the fast, ate by 10am, and I’m headed to the 10:30.
Well, I am guessing you will have met the 1 hr. fast but, I am also guessing you will get this post way too late to do you any good.
To be sure to make the 1 hr. fast I suggest you eat a minimum of 45 minutes before the start of Mass that way you get into the habit of being prepared.
You could also just look at your watch right before Communion to see if you have met the 1 hr. fast (give or take about 5 minutes). I know I have done that when I go to weekday Mass.
It is not required that we receive communion every time we go to Mass. If you have concerns about whether you’ve met the one hour fast, don’t receive communion at that Mass. It will probably help you remember better next week. Another option would be to attend a later Mass.
I have always started the fast 1 hour before mass starts. While not required, I know for sure I’m covered
On a Sunday, 30 minutes prior is almost sure to cover you, on a daily mass, it can be cutting it close sometimes.