Searching for emails **Older** than a relative date

So this has been at least partially covered in this topic, but I can’t seem to figure out how to create a search folder that looks for emails older than a number of days/weeks/months. You can search within a relative timeframe (e.g. within the last week), but I can’t search for emails older than 3 months. I know that I can make a hardcoded search folder using an extremely old date for the beginning search date and 3 months ago for the end search date, but I don’t really want to have to manually update this every day to keep it up-to-date. I know that this is a feature many other email clients already have.

On a related note, while, “Received Within Date,” has a few preset relative timeframes (1 day, 3 days, 1 week, 2 weeks, 1 month, 2 months, 6 months, 1 year), the “Custom range” setting just appears to put us right back to hard-coded date ranges, instead of being able to tell the search folder to look for something like emails within the last 21 days.

Am I missing something, or is this something not currently available. If it is not currently available, is this currently being addressed?

Thanks!