You have misunderstood what

[0-9(th)?(st)?(nd)?(rd)?]
is doing. It says any one of these characters and so if you say 20th June then it is matching only "h" and not "20th". I guess what you meant was something like

[0-9](?:th|st|nd|rd)?

With a complicated regular expression it is worth using /x and putting lots of white space in so that you can easily see what is going on.

In reply to Re: $1 by Odud
in thread $1 by Anonymous Monk

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