Re: How long do new packages take syrup?
If you feed a 3 lb package ~2 quarts of syrup a week, they won't starve, but won't build up much either. Give them this "sustenance feeding" and let them work for the rest if there is a flow on. Adjust as needed for no flows, or mostly foundation. In most cases, a month of supplemental feed should be plenty enough to give them a good head start. They might do fine without any feeding if local flows can sustain them.
After 40 years of beekeeping, I've come to realize that the bees can fix most of my mistakes.