I watched this pair of blue tits courting yesterday - initially I thought it was an adult feeding a chick, but on looking more closely it was clear that they were two adults. What I presume was the female (on the right), was crouching and shivering her wings, and the male would land on the branch next to her and feed her, just like he would do for a fledgling. From what I've read, this behaviour happens immediately prior to mating:

Taken with E-5, 50-200, 1.4xTC

Taken with E-5, 50-200, 1.4xTC
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