Our night time routine for our DD who is 5 mths old is:
Bath or Shower everynight btw 6/6.30
Bottle 7pm
Bed btw 7.30-8pm (depends on how she has been during the day)
Dreamfeed 11pm

Sounds like a similar situation that my DD fell into however, she was a terrible daytime sleeper, so I think she became overtired at night time, as such we follow a 'routine' now during the day, which is like this:

7.15am up/change (DD wakes at this time every morning now)
7.30am - bottle
9.30am sleep until 11.30am (if she wakes before, I try to get her to go back to sleep and if she is calm or just talking to herself I leave her in bed until 11.30am. If she is crying I will get her up)
11.30am Bottle
1.30pm - sleep until 3.30pm (as above)
5.30pm - catnap

Then night time routine