I need to upgrade from a beginners flute to one that will take DD up to grade 8 and beyond. She is about to take grade 6. Any suggestions or recommendations. Thank you.

Where are you? We're in Berks and there is a fantastic wind instrument shop (Dawkes) in Maidenhead who really seem to know their stuff, we've used them to service our DD's flute. We have a fairly basic Yamaha I think, DD will only be doing G5 soon so I'll be watching your thrrad closely

Edit: just read your older / other thread about flutes and see that someone else has already recommended Dawkes

You need good advice and to go somewhere where you can play them - a solid silver mouthpiece is often recommended but the price can vary.
Different makes suit different flautists - we got another Yahama. We kept the beginner's flute so when one is being serviced etc. the other is still available for practising.

Another vote for Dawkes if you in commutable distance.

My DD plays sax and we got to the point where the rental was holding her back. They have a great soundproof room where you can record yourself trying various instruments and then play back. It can mimic small room to concert hall with techy jiggery pokery. There was a surprising difference between instruments in her price range so you do need to try a few.
Their service/repair is really good too - we have become the family that people pass on languishing instruments to and each one has required a major overhaul to make it playable. They have done a great job every time.

We were in the same position a few years ago. You probably need to set a budget and talk to her teacher about what may be appropriate, including open / closed hole. We ended up spending over £2000 on a Muramatsu EX86 it was a lot of money but, as DD is now studying flute at a music college, a good investment. It was her teacher who said it might be a good idea to make that leap.

Get her to try several, if it’s doable for you Just Flutes in Croydon is a good place to start. Don’t forget if she’s at a state school you may be able to use the Assisted Purchase scheme and not pay VAT.

Thanks to everyone who has given advice. It's really helpful. We have recently spent a lot on a new piano so need to be sensible with cost, (we weren't with the piano and blew the budget) but I also want to get something that will see her through. We are in South Herts.

Guest55, which Yamaha did you upgrade to? Her sister is going to get the student flute

It's a Yahama 312 but the exact model isn't on it - I think the current 312 has different letters anyway. It has a solid silver head and silver plated body - DS has had it about 10 years now and it still plays well. He did well at grade 8 whilst stll at school.

Thank you. We tried out an Azumi AZZ3RE today when we took DDs flute to be serviced which seemed good but £1,779 and solid silver. We are only 20 to 30 miles from Dawkes so will probably have a look there as well. Had only planned to spend around £1,000 but maybe that is naive?

No - the current price of DS's flute is under £1 000 and remember you should be able to get it VAT free through a music centre or school.