The Welcome Hills has plenty of Lady's Smock. It prefers damp areas.
This morning I saw 3-4 males and 2 females. Chasing these butterflies in the hope of seeing them alight is good fun but seldom productive. My technique is simple: find a Lady's Smock in the sunshine, then wait for the butterfly to come to you. They don't rest long though so you have to be ready and quick.
Here are today's pics. I didn't get a pic of the female though. Maybe next time.
Below are pictures of one of the Orange Tip's eggs from a few years ago.
The final pic (below) is the underside of the Orange Tip - both male and female have this mottled green marking.