Sometimes they can be seen drinking at puddles in the afternoon, but last year that didn't work for me ( I actually created some on the bridal path and waited, to no avail ), so views were restricted to binoculars and photographs from long digital zoom shots last year.
They tend to fly from around Midday as long as the weather is half decent, from about mid March.
I managed to photograph some I found at Chaddesley in 2012 from a reasonable distance, but wanted to study them a little more closely if possible, as it is really the underside of the underwing which defines this species from the slightly later flying Light Orange Underwing.
After nearly giving up, I eventually managed to net one and took it home to study in my magnifying jar. After a record shot and returned it to the spot it was trapped, from where it flew quite happily to join the dozen or so chums that were flitting around the plantation.