Both of my babies were Gina Ford babies. Dd was fantastic with it, ds struggles a bit as his routine goes wonky due to nursery runs etc for older sister. He is 9m and naps between 10-11, then 1:30-3:00. In bed by 6:30.
To break the cycle, cut the afternoon nap, try super early night. 5:30 / 6:00pm.
I have a couple of questions though:
Do you have a pitch black bedroom? 5-6 am waking can be related to morning light coming through. Most fabric shops has black out curtain fabric and gaffa tape it to the window frame if needed to. I heard Gina Ford consultancy don't send the consultant out unless ou installed the proper black out curtain.
Do you wake her at 2:30? Perhaps if she can sleep longer, let her sleep a bit longer until 2:45 or even 3. Then cut the late afternoon nap definitely. Try dinner at 4:30/5:00pm, bath by 5:30-6:00, milk and and in bed by 6:30, definitely by 7:00 at latest. I agree 5h is way too long for a wake time. In the afternoon, I would cut back on vigorous activities and have a mellow walk or gentle play to make her last longer.
Early night does not always make the baby wake early. It gives them more restful sleep cycle than just passing out and going into deep sleep being over tired.
What goes on between 5:45-7:15? Often that is when the dad comes home and that just stirs things with too much excitement. Sorry dad, but it just does not work....
Try giving your girl more carbo throughout the day, definitely more for dinner, and by this I mean mashed potato, or polenta, rice (try softly cooked paella rice than basmati) something filling for longer. I noticed pasta does not keep my lil man full for a long time. Also around that time my milk supply was getting low (due to me being tired) so I introduced top up with formula.
I love Gina Ford, but sometimes, I felt their natural cycle was pushed a little too hard. Check out baby whisperer online forum and see a sample routine for 8m baby. I found through my babies that 7:00pm - 6:30/7:00 am night sleep would still work as long as you don't let your lil one sleep for more than 3h during the day in total, no matter when you put them to bed and as long as he was awake after 3:00 pm.
Sorry for a long post....