if lo is still taking 4 naps how long is each nap - i do think that 4hrs naps is pushing it a little and maybe 3 to a max of 3.5 hrs would be better to keep the night/early wakings away kwim? at 8 months my lo could nap no more than 2.75 hrs / day so going by that i would estimate that amount for your lo - but as stacy said all lo's are different and have their own unique 'clocks' so really it will be trial and error, if you still have wakings after some time cut it down by another 15 min or so. don't be deterred by a setback or two...rome wasn't built in a day..or a week for that matter
keep doing what you are doing - an excellent job it is at that may i add!
i also agree with stacy as the pm nap will help your lo get that longer A time before bedtime. the morning nap is 'supposed' to be the shortest as it often looked at as an extension of night sleep and if it runs too long may also cause early wakings as lo will be making up for the lost night sleep in the morning nap.
