Timeline Does Not Like Linked Date

I have two linked tables and am using one of them to generate a timeline chart.
The first date (Let’s call this Start Date) is entered directly into the date field , The second date (Let’s call this End Date) is from a rollup max value (I know that you cannot use Lookup) with a limiting criterion. When checking this second date that it identifies it as a correct date format it is OK.
When I try to create a timeline chart using the Start and End dates, it does not detect the End date and therefore no timeline.
Note, if i put the duration in the linked table and perform rollup again then select duration instead of end date for timeline, it does not like that either.
Note, all dates are correctly identified as dates and not date or number arrays
Can you please help
Alfred

I can reproduce the issue. @Leo.Shi Do you want to take a look at this?

There is an easy workaround though: Add a formula column and quote the rollup column (. Then use this formula column in the timeline view.

Workaround works well - Thank you

This is a bug, we will fix it.