Thanks for your feed-back. This one was much smaller and without the usual markings

Brimstone.

Canon 5D - EF 70-200 f4 IS and 12mm extension tube. This is my favourite set up for butterflies.

None so far this year, and very few last year.

This garden visitor had a flight path similar to an Orange Tip. Upper wing surface appeared to be plain white, underside as you can see from photo has a tinge of yellow to front edge.