I have seen Small Tortoiseshells be the subject of much discussion on various social media over the past couple of years, especially with regard to early hibernation and whether this is masking true numbers.
As with many other comments I have seen, it was certainly the case that good numbers appeared out of hibernation around my patch despite being thin on the ground the previous summer.
This species, along with Comma, also provided me with my first ever February Butterflies during that unseasonably warm spell we had late last Feb.

- Small Tortoiseshell - Wagon Lane 22.02.2019
After that, the weather returned to more typical conditions for the time of year and it was later in March that they reappeared again, a much more usual time for around here. By this time the spring blossom was fully out which gave me the opportunity for some of my favourite 'butterfly on blossom' shots.

- Small Tortoiseshell - Wagon Lane 23.02.2019

- Small Tortoiseshell - Wagon Lane 23.02.2019

- Small Tortoiseshell - Wagon Lane 29.02.2019
The first summer brood started appearing around my local spots in mid June...

- Small Tortoiseshell - Bickenhill 16.06.2019
...after which they would pop up in ones and twos at most places I went to.

- Small Tortoiseshell - Heddon Valley 25.06.2019
By the second half of July I was seeing anything from half a dozen to a dozen or more at my local sites, more than I have seen for a few years now.

- Small Tortoiseshell - Castle Hills Solihull 21.07.2019

- Small Tortoiseshell - Castle Hills Solihull 21.07.2019
These numbers continued through to late August, after which they all disappeared.

- Small Tortoiseshell - Castle Hills Solihull 26.08.2019
I am not sure if these later ones were a second brood or if they were simply later emerging individuals of one brood but whatever the case they definitely staged a bit of a recovery around here in 2019.
Cheers,
Neil.