But Feier milk has more calories than any weaning food, so if you have a hungry baby, the best thing you can give them is more milk. Which is hard on us, sadly.
The other thing to watch out for is the 4 month growth spurt - babies tend to get quite unsettled around 4 months and start waking up more and demanding more milk, but it doesn't mean they need solids, and if you ride it out they settle down again, IMVHO. DS1 certainly did, and Orbit is now nearly 5 months and is definitely settling down from his mad feeding period.
Personally (and you all know this is a favourite topic for me ) I can't see how a baby can possibly be deemed ready for solids, from an evolutionary perspective, while it can't sit up independently or grab food, or most importantly, while its reflex is to spit them out. Until they've lost their tongue thrust reflex, then surely solids can't be needed? Otherwise, surely their instinct would be to swallow, not spit?
Anyway, to each their own weaning date, but that's my two cents.