Hello,
My lo's almost 5 months now, but I think we went to a 3.5 hour routine around 9 or 10 weeks. It sounds like your lo is ready for a little longer routine. I'll post ours just for an idea for you. Also, I think "iykwim" means, "If you know what I mean." I remember the 3.5 hour routine being a little tricky in the beginning as my lo still couldn't handle too much awake time and didn't always nap for 2 hours, so sometimes we would have some awake time before he ate. I do not breastfeed so I know it will be a little different for you and you could still do the dreamfeed. We tried the df a few times but my lo still woke up at the same time regardless so we don't do it.
7/7:30am-Wakes on his own/Eats
9:00am-11:00am-Nap (approx. times...sometimes 15 min. down/up earlier/later)
11:00am-Eat
12:45/1ish-2:30-Nap
2:30-Eat
4ish-5ish-Nap (Catnap, usually 45 min.)
6:00-Half of his bottle (this is all he'll take here), then bath
6:20-Finishes bottle and bed at 6:30pm
He sleeps through until 7/7:30am