Well, as for the 4 hr easy, she may well be ready! The best way to know is to slowly stretch out the feeds and see how she does with naps etc. But you want to do it gradually - do you have the latest book? There are some nice suggestions for the transition in there.
With respect to starting solids, I personally really feel that babies should wait until they're 6 months old - size has nothing to do with it. I've known some really huge babies that were exclusively bf to 6 months with no problems. And starting early can cause more problems that it's worth - tummies aren't mature enough to digest solids, so she might get gas or wake from an upset stomach, not to mention the association with allergies. Most pediatric agencies are strongly recommending waiting until 6 months too....just a thought...
Why do you feel you're losing your milk supply? FOr most women, around 3-4 months, your milk supply really stabilizes - you stop leaking, feeling engorged, that sort of thing. So some moms think it means their supply is going down, but as long as the output is good (dirty diapers and weight gain), you don't have to worry.
All this to summarize: if you feel like she's ready for a 4 hr cycle - try it! But slowly! Keep breastfeeding, if you enjoy it, and wait for 6 months to start solids, if you're agreeable. HTH!
