Btw, I just wanted to say thanks to everyone who advised on the off/on lead question I asked the other day. I've ordered a longer lead but remembered in the meantime I have one of those retracting leads we bought and never used.
Since your advice I've been doing this: off lead most of the time but when we see a dog coming I call her and put her on lead. We then do a lot of work on 'stay with me' and working on ignoring the other dogs/not bounding over. Depending on the dog, she will ignore entirely or say hello if they're interested, and with other dogs who are keen to play, I've let her off for a bit.
This has made such a difference to our walks - you were all right in that she was learning she can sometimes ignore me. She's been much much better at coming the first time I say her name, and in the couple of interactions where I've let her off with the other dogs, she also comes back to me first time and doesn't need to be put on the lead to come away on my command.
It's made such a difference to both of us in such a short space of time - I've felt much less worried about the possibility of her not coming back, and it's reinforcing her recall in a positive way each time.
Thank you all!