Battery life poor since 15.5 update

Since the iOS 15.5 update arrived on my iPad Pro 9.7 I’m having terrible battery life. Previously a full charge would last 2 days but now I’m charging twice a day - battery will go from 100% to 15% in a few hours. I’m not using the device to view movies but just general internet browsing & emails.

Closing all apps makes a very, very small difference but I require those apps for my work.

I have restarted the device & turned it off then on again with no difference.