unexpected behaviour with updateInformation on (? Time) and (? Date) and (? DateTime)

I'm encountering unexpected behaviour with updateInformation in combination with ?Time, ?Date, and ?DateTime values.

First, updateInformation on ?Int behaves as follows (testing (updateInformation [] ?None)):

1. starts with a blank editor, confirming gives value ?None
2. if you fill in a value v and continue, you obtain value (?Just v)
3. if you fill in a value and make the editor blank again, confirming gives value ?None

Repeating this on ?Time (or ?Date or ?DateTime) does not allow you to continue with a blank content, so steps 1 and 3 above are impossible.

I expected some sort of check box that if marked lets you proceed to edit a value v in order to have a (?Just v), and when unchecked have ?None. I tested this with a record type:

:: H = {h::Int}
derive class iTask H

and that is the case. Also for algebraic types:

:: G = M | F
derive class iTask G

it works via going back to Select... in the created drop-down list.