Breast milk supply tanking

I am currently on vacation and my my milk supply has just completely depleted. I usually pump 12oz every 3 hours and now I’m getting at most 3oz every 2/3 hours. Any ideas what could be doing it? Only changes have been I pump one less time per day since my baby is sleeping through the night before he got up once. I have 1,100 ounces at home so I’m not too concerned once I get home but here I am pumping every two hours to keep up with his 6 ounce bottles and it’s nerve racking!

Update: I talked to a lactation consultant and she told me to pretty much live on the pump until it improves. Today I started to get 6 ounces each pump which was perfect considering that’s how much he is eating. Thankfully I am home now and have my freezer stash so he only had to have one bottle with formula in it.