Oscar was a very easy breast to bottle of EBM and back again baby and a total guzzler. I went back to work at 4.5 mths and he was on 7,11,3,7,DF at 11pm and STTN at this stage.
When we introduced solids at 24 weeks on advice of paed as haemoglobin was low we slowly started reducing the 11am feed and then phased it out completely by 7-8 mths ish (its 7 yrs ago so I don't remember LOL). But at his best, Ozzie was guzzling all I pumped in work between the 11am feed and the 11pm feed (around 13-15 oz a day - I was a prolific pumper as well LOL over two pump breaks).
Emma was on 5 feeds a day at 5-8 mths as well and it was also the 11am feed I dropped first in her case as I was back in work at 7.5 mths and didn't have the time to pump so didn't and fed before and after work 7am and 3.30pm ish and in the meantime she drank water only. She would never take a bottle!
I honestly think tummy troubles due to solids and/or distracted feeds are the main culprits of feeding very frequently at this age - that or snacking/mummy as dummy....I would stretch the feeds for sure as you are and intro the DF too, whichever way works - we've done one with bottle (Ozzie) and one direct from the breast. Both gave good results with these particular babies xxx