I breastfed whenever possible, but I also liked to have a backup supply in case I was going out somewhere and couldn't bring Baby with me. I'm going to use my daughter as my example, cuz I had to build up a HUGE supply for her. For the first month, I exclusively breastfed...even if it meant bringing her into bed with me in the middle of the night and latching her, and closing my eyes. I'm a light sleeper so when she was done, I always just laid her back down. We fed in the night using side-laying position. I did this so that she could establish her own supply. Breastmilk is supply and demand, and I wanted to make sure my breasts were producing enough for her to eat before I sat with my pump to get more.
I would NOT recommend too many bottles overnight, especially in the first month or two, as you're going to get seriously engorged, and that can be painful, lead to clogged ducts and mastitis, and it can actually DECREASE your supply.
If you want to build a little bit of a supply, allow your baby to exclusively breastfeed the first month to establish their own supply. After the first month, follow up your baby's feed with 5-10 minutes of pumping, or until a second letdown. This will help increase your supply by an ounce or two and will help you be able to build up a stored supply. Another thing you can do in the first month is feed your baby from one side (once your milk comes in) and pump from the other side after the feed and store the pumped supply. Your breasts will both be empty and ready to feed for next feed session, but do this ONLY on the first feed of the day. That is when you'll have the most milk.
I hope I'm making sense. Sometimes I ramble.
Personally, my daughter fed, and then I pumped til empty for the first feed. If she didn't wake before I was engorged, I pumped, then fed her the expressed milk when she woke if I didn't feel full enough (all after first month).
When she was 6 months old, I went to Florida for a week without her. Just by pumping an extra 5-10 minutes after she fed, or pumping to a second letdown, I was able to increase my supply by a few ounces. I started in July/August of 2011 and by the time I left for Florida, she had 600oz to live off for the week that I was away from her. She didn't receive a single ounce of formula that whole week and actually still had about 75-100oz leftover when I returned from Florida.
So, let's see if I can summarize:
1. Breast exclusive in the first month to allow baby to establish his own supply, or feed from one side and pump from the other.
2. After first month, pump for 5-10 minutes, or until second letdown to gain an ounce or two for storage. After a few days, your breasts will automatically produce this, and eventually, you'll gain more of a supply and produce even more if you continue this (For example, if you can get 3oz, pump for 5-10, which may get you up to 5oz. Eventually, you'll produce 5oz no problem, but if you keep this up, you'll start to pump out 5oz, and if you keep pumping, you can get up to 7oz.)
3. Store any pumped milk in a deep freezer. If it's a top freezer, it's only good for about 30 days. A deep freezer, it's good for 6-12 months.
Those who say it became an ever-increasing bottle feed probably didn't let baby establish their own supply before they started pumping. Baby will ALWAYS get more milk out than a pump will. They also say to do exclusive breast in the first month to establish a proper latch, as alternating can sometimes make them confused and they may shape their mouth around your nipple as if it's a bottle rather than the breast, which can lead to decreased supply, cracked and bleeding nipples, etc.
But yeah, if she was with me, she was latched to the breast. If I was away from her, she had the breastmilk in a bottle.